Tag Archives: big bang

Bright galaxies help solve mystery about early universe

This deep-field view of the sky (center) taken by NASA’s Hubble and Spitzer space telescopes is dominated by galaxies – including some very faint, very distant ones – circled in red. The bottom right inset shows the light collected from one of those galaxies during a long-duration observation. Image credits: NASA/JPL-Caltech/ESA/Spitzer/P. Oesch/S. De Barros/I.Labbe

For all its mind-bending features, the universe is a pretty ordered place. Stars and planets are neatly arranged into solar systems; solar systems have vast swaths of space between them and are themselves arranged into galaxies. Space is also transparent and decently lit by stars, which is nice because it allows us to see at large distances, and, because of how light works, also allows us to see in the past.

But it wasn’t always like this. In its earlier days, the universe was much more tumultuous. For the first 377,000 years, it was a soup of various types of matter and antimatter, finally becoming cool enough for individual atoms to form — but it was still dark and murky. Even some 1 billion years after the Big Bang, when the universe had become transparent, there weren’t too many sources of light because it takes such a long time for mass to collapse into stars and galaxies, though light had been sparked nonetheless.

Here’s the thing, though: while Dark Ages of the universe started around 377,000 years after the Big Bang, there was still some radiation. Something started exciting the hydrogen with radiation, ionizing it and producing light. Astronomers are not really sure how this happened, though.

No one really knows when the first stars in the universe came to be. There is evidence suggesting that they formed some 100-200 million years after the Big Bang — but did they have enough energy to produce this ionization phenomenon? That’s hard to say.

Now, a new study finally sheds some light on this issue.

“It’s one of the biggest open questions in observational cosmology,” said astronomer Stephane De Barros of the University of Geneva. “We know it happened, but what caused it? These new findings could be a big clue.”

In an attempt to answer this question, De Barros and colleagues directed the Spitzer telescope at two separate regions of the night sky. The telescope detected 135 galaxies that formed just 730 million years after the Big Bang, and they were very different from the galaxies we’re used to seeing.

For starters, they were very bright in two specific wavelengths of infrared light produced by ionizing radiation interacting with hydrogen and oxygen gases within the galaxies. This suggests that the galaxies were dominated by hydrogen and helium, containing very small amounts of  “heavy” elements (like nitrogen, carbon and oxygen) compared to stars found in average modern galaxies. But the most surprising (and important) finding was that they were so bright — much brighter than researchers anticipated.

This suggests that average galaxies at the time were much brighter than average galaxies are now.

It’s the first study to document the brightness of galaxies from this period. Although these galaxies were not the first generation, they are still a very old group which could shed new light on this reionization era, a key process of the evolution of the universe.

The fact that these observations could even be made with Spitzer was surprising, researchers say.

“We did not expect that Spitzer, with a mirror no larger than a Hula-Hoop, would be capable of seeing galaxies so close to the dawn of time,” said Michael Werner, Spitzer’s project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California. “But nature is full of surprises, and the unexpected brightness of these early galaxies, together with Spitzer’s superb performance, puts them within range of our small but powerful observatory.”

“These results by Spitzer are certainly another step in solving the mystery of cosmic reionization,” said Pascal Oesch, an assistant professor at the University of Geneva and a co-author on the study. He also adds that the James Webb telescope, which is set to launch in 2021, will study these stars with a mirror 7.5 largers than Spitzer’s. “We now know that the physical conditions in these early galaxies were very different than in typical galaxies today. It will be the job of the James Webb Space Telescope to work out the detailed reasons why.”

The study has been published in the Monthly Notices of the Royal Astronomical Society.

Illustration of planetary nebula NGC 7027 and helium hydride molecules. Credit: NASA.

Astronomers finally find the earliest molecule in the Universe

Illustration of planetary nebula NGC 7027 and helium hydride molecules. Credit: NASA.

Illustration of planetary nebula NGC 7027 and helium hydride molecules. Credit: NASA.

About 100,000 years after the Big Bang, a blink of an eye on the universe’s timescale, the primordial atoms helium and hydrogen combined to form the first molecule, helium hydride. Physicists believe that this molecule’s formation helped the young universe cool down, allowing stars to form. Helium hydride should still be present in some parts of the modern universe but it has never been detected in space — until now.

“The lack of evidence of the very existence of helium hydride in interstellar space was a dilemma for astronomy for decades,” said Rolf Guesten of the Max Planck Institute for Radio Astronomy, in Bonn, Germany, and lead author of the study published in the journal Nature this week.

The discovery was made by NASA’s Stratospheric Observatory for Infrared Astronomy, or SOFIA, the world’s largest airborne observatory. Flying up to 13,700 meters (45,000 feet), SOFIA makes observations above the interfering layers of Earth’s atmosphere, taking off and landing for each observation. Inside a modified Boeing 747SP jetliner, scientists fitted state-of-the-art instruments such as the German Receiver at Terahertz Frequencies (GREAT) instrument that can be tuned to the frequency of helium hydride, similar to tuning an FM radio to the right station, and search for it in space.

NASA researchers pointed SOFIA’s instruments onto a planetary nebula located 3,000 light-years away called NGC 7027. Since the 1970s, scientists had suspected that this is one of the best places to look for helium hydride but until now they were lacking the proper tools.

“This molecule was lurking out there, but we needed the right instruments making observations in the right position — and SOFIA was able to do that perfectly,” said Harold Yorke, director of the SOFIA Science Center, in California’s Silicon Valley.

Finding evidence of the primordial molecule validates our current models of how the universe came to existence. According to the theory, after the universe started to cool down, hydrogen atoms interacted with helium hydride, leading to the creation of molecular hydrogen — the substance primarily responsible for the formation of the first stars. Once the first stars appear, they could forge heavier elements that would eventually disperse into the universe forming asteroids, planetoids, and planets.

“It was so exciting to be there, seeing helium hydride for the first time in the data,” said Guesten. “This brings a long search to a happy ending and eliminates doubts about our understanding of the underlying chemistry of the early universe.

Stephen Hawking: before the Big Bang there was nothing

Professor Stephen Hawking is a world-renowned British theoretical physicist, known for his contributions to the fields of cosmology, general relativity and quantum gravity. He recently sat down with Neil Degrasse Tyson on his “Star Talk” show and it didn’t take long for the talk to get really deep, down to the very origin of the universe but also what came before it.

When asked “what was around before the Big Bang,” Hawking was very uncompromising, simply answering that there was “nothing.” The physicist goes on to explain that Einstein’s Theory of General Relativity states that time and space form a continuum, “which is not flat but curved by the matter and energy in it.”

To answer what happened before the Big Bang, Hawking took a so-called Euclidian approach to quantum gravity to describe the beginning of the universe. What does that mean? According to Hawking, this means that ordinary time is replaced by imaginary time, and this imaginary time “behaves like a fourth direction of space.”

Hawking’s model claims that the history of the universe is a four-dimensional curved surface, just like the surface of the Earth but with two additional dimensions. What’s more, the boundary condition of the universe (the known and constraint value that must be true for the problem that you are working)… is that it has no boundary. In other words, there was no time before the beginning of the universe.

“One can regard imaginary and real time as beginning at the South Pole which is a smooth point of space-time where the normal laws of physics hold. There was nothing south of the South Pole so there was nothing around before the big bang,” Hawking explained.

That’s a pretty mind-blowing statement and although it comes from a foremost authority in cosmology like Hawking, the jury is still out on whether that was really the case or not.

 

 

 

Breakthrough in the search for dark matter from the first ever stars

Using radio antennas no bigger than a hotel fridge, a small team of astronomers managed to glimpse into the dawn of time, and they published their findings just yesterday. But if that wasn’t dramatic enough, a new paper today reports that the same results are a paradigm shift in an even more obscure area — the readings are our first direct evidence of the existence of dark matter and yield important clues on its nature.

Scientists may have caught a glimpse of the earliest stars in the universe.

[Editor’s note] We’ve covered the first part of the findings yesterday, and you can read it in-depth here. But, if you happen to be suspicious of links or you like Andrei’s skill with a keyboard, here’s the summed-up version:

Why yesterday was a good day for science

Although it happened billions of years ago, researchers have been able to infer quite a lot about the Big Bang and the following eons. Scientists theorize that right after the big event, everything was dark, and it took a few hundred million years for the first stars to form out of the primordial soup of matter. So far, astronomers haven’t been able to pick up any signal from these stars, as our telescopes just weren’t sensitive enough. Now, using the Experiment to Detect the Global Epoch of Reionization Signature (EDGES), an array of three telescopes from remote Australia, researchers have captured the first glimpses of these ancient objects.

The oldest galaxy we’ve observed emerged around 400 million years after the Big Bang. This signal is the first thing anyone has spotted in the interval between that galaxy was formed and the so-called cosmic microwave background, 380,000 years after the birth of the Universe.

“This is really the only possible probe that we have of the time before the stars,” says Bowman, who is an experimental astrophysicist at Arizona State University in Tempe.

The small antennas in the Australian outback. Credits: CSIRO.

Before the first stars formed, the atoms’ internal states were in microwave equilibrium — they absorbed just as much radiation as they gave out. As the first stars formed, they produced light which disrupted this equilibrium, enabling the atoms to absorb more than they gave out. This is what astronomers have identified yesterday. It gives a unique insight into those early days, showing that, for instance, the initial hydrogen was much colder than originally thought (since the absorption signal was twice stronger than expected, and this correlated with temperature).

Why yesterday made for a great day for science… today!

This also shines new light on the so-called dark matter, a mysterious and invisible form of matter spread through the cosmos.

The early stages of the Universe. Credits: N.R.Fuller/National Science Foundation.

The signal Prof. Bowman’s team picked up was a radio signal at a frequency of 78 megahertz. The width of this signal’s profile was by-and-large consistent with what they expected to find, but it also had a larger amplitude that they expected — which corresponds to a deeper absorption of the signal in space. They concluded that this means the primordial gasses in the early universe were colder than we’ve estimated, reported on the finding, and presumably thought that was the end of it.

However, that one tiny detail could provide us with the first direct proof of the existence of dark matter, and the first actual clues about its nature. It’s the first direct piece of data we have on dark matter since we’ve first started thinking about it, over one century ago. In other words, that tiny detail yielded a breakthrough in the field.

“I realized that this surprising signal indicates the presence of two actors: the first stars, and dark matter,” says Prof. Barkana, Head of the Department of Astrophysics at the Tel Aviv University, who published the paper detailing the link between this signal and dark matter.

“The first stars in the universe turned on the radio signal, while the dark matter collided with the ordinary matter and cooled it down. Extra-cold material naturally explains the strong radio signal.”

Basically, all we know of dark matter is that it exists… and that we can’t see it. We know its there because we can measure its gravitational effect, but that’s about it. That’s why, in Prof. Barkana’s words, dark matter “remains one of the greatest mysteries in physics.”

“To solve it, we must travel back in time,” he says. “Astronomers can see back in time, since it takes light time to reach us. We see the sun as it was eight minutes ago, while the immensely distant first stars in the universe appear to us on earth as they were billions of years in the past.”

Based on observed gravitational effect, physicists expected dark matter particles to be very heavy, but Prof. Barkana’s results suggest that they must be less than five times as massive as a hydrogen atom. The finding has the potential “to reorient the search for dark matter,” says Barkana.

But this isn’t the only plausible explanation, and we’re still waiting for the dust to settle before any definitive conclusions can be drawn. First, as always, is sheer instrument error. A confirmation would be highly useful, given how fine the measurements the EDGES device was performing. Even the tiniest error in calibration or measurement could distort the signal, and although the researchers are confident they’ve done their best to ensure that no error slipped in, they’d also welcome any confirmation.

“We’re eager for others to confirm the result,” Bowman added.

One definitive piece of evidence in favor of Barkana’s theory could be picked up with a large array of radio antennas. He says that, according to his model, the dark matter should have produced a very specific pattern of radio waves.  Luckily for us, one such array, the SKA, the largest telescope in the world, is already under construction — if it picks up on the signal, the SKA “would confirm that the first stars indeed revealed dark matter,” concludes Prof. Barkana.

The paper, “Possible interaction between baryons and dark-matter particles revealed by the first stars” has been published today in the journal Nature.

Bowman’s paper, “An absorption profile centred at 78 megahertz in the sky-averaged spectrum” has been published in the journal Nature.

 

Star.

We’ve just found the earliest traces of hydrogen, showing when the first-ever stars ignited

MIT and Arizona State University researchers are hot on the heels of the Universe’s first stars: they’ve traced the faint signals of hydrogen gas energized by stellar radiation just 180 million years after the Big Bang.

Star.

Image via Pixabay.

Where does everything come from? That’s one of the questions people have been burning to answer since times immemorial. It’s a hugely complicated question, but science can offer some bits and pieces to start cobbling the answer together. A paper published today by MIT and Arizona State University researchers uncovered a fundamental one such piece: the earliest evidence of hydrogen gas and the earliest evidence of stars igniting that we’ve ever seen.

The gas from whence we came

Using a table-sized radio antenna plopped down in a remote part of western Australia, dubbed EDGES (Experiment to Detect Global EoR Signature), the team managed to pick up trace signals generated by hydrogen gas, just 180 million years after the Big Bang. This is the earliest evidence we’ve ever seen for the presence of hydrogen in the early universe — a very important find, considering hydrogen is the simplest, and thus first, atom out there. The team was also able to determine that by this time, the gas bore traces of the first stars in the world.

“This is the first real signal that stars are starting to form, and starting to affect the medium around them,” says study co-author Alan Rogers, a scientist at MIT’s Haystack Observatory.

“What’s happening in this period is that some of the radiation from the very first stars is starting to allow hydrogen to be seen. It’s causing hydrogen to start absorbing the background radiation, so you start seeing it in silhouette, at particular radio frequencies.”

The EDGES instrument was designed to pick up radio signals generated during a time in the universe’s history known as the Epoch of Reionization, or EoR. It’s during this time that we think the first sources of light (such as stars) sprang up in the world, from a sort of cosmic primordial soup made up mostly of hydrogen gas. Not much else was happening before this time, mostly due to a lack of energy to change objects in the universe: hydrogen, for example, was virtually invisible, as its energy state made it indistinguishable from the surrounding cosmic background radiation.

Horsehead.

The dark Horsehead Nebula in the constellation Orion. Hydrogen corresponds to red.
Image credits Ken Crawford.

But the birth of these sources of light and energy ionized the hydrogen gas, changing its energy state, and making it release energy as radio waves — and that’s exactly what EDGES was designed to pick up.

However, not all went according to plan. When the team looked at the frequency range the antenna was designed to pick up, between 100 to 200 megahertz, they hardly picked up any signal.

Void-cold

One explanation they came up with is that the theoretical models which we used to calculate what emissions this early hydrogen would give off overestimated the gas’ temperature. So they re-crunched the numbers, this time assuming that the hydrogen and its environment were at about the same, lower temperature. They decided their best bet was to search the 50 to 100 megahertz frequency range, so they returned their antenna and flipped the switch again.

“As soon as we switched our system to this lower range, we started seeing things that we felt might be a real signature,” Rogers says.

The device picked up a flattened absorption profile (i.e. a dip in the radio wave-spectrum) centered around 78 megahertz. Rogers adds that the frequency corresponds to “roughly 180 million years after the Big Bang”, adding that “this has got to be the earliest” detection of a signal from hydrogen we yet have. To put things into perspective, we know that the universe is at least 11 billion years old, and most estimates place its age upwards of 13.5 billion years.

The radio profile matches theoretical predictions of a star-hydrogen interaction. These early stellar bodies poured ultraviolet radiation out into the void, ionizing any surrounding body of hydrogen. As a result, the gas began to absorb background radiation, which changed the spin on its single electron. Ultimately, this change made the atoms emit, rather than absorb, radiation, at a characteristic wavelength of 21 centimeters, or a frequency of 1,420 megahertz — becoming, in effect, ‘visible’ for the first time.

Red-shift affected these waves, so by the time it reached present-day Earth, it was somewhere in the range of 100 megahertz.

But the dip in the radio spectrum was also stronger and deeper than the models predicted — suggesting that the hydrogen was indeed colder than previously assumed. The team estimates that the hydrogen gas and the universe as a whole must have been twice as cold as previously estimated, at about 3 kelvins, or -270.15 degrees Celsius / -454 degrees Fahrenheit.

The edges of discovery

Haystack EDGES.

Image credits MIT / Haystack Observatory.

The research is likely the best window we’ll have into the universe’s early history for a long time to come. It took an incredible scientific effort to obtain these results. It took years of hard work for engineers and scientists to design, re-design, and re-calibrate the EDGES instrument to even have a hope of picking up on these signals. Peter Kurczynski, program director for Advanced Technologies and Instrumentation in the Division of Astronomical Sciences at the National Science Foundation, the organization that built EDGES, compares it to “being in the middle of a hurricane and trying to hear the flap of a hummingbird’s wing.”

“Sources of noise can be a thousand times brighter than the signal they are looking for,” he explains.

It was built in the middle of Australia’s nowhere (which has to be at least nowhere squared) because it was the most remote place they could get to — and that limited interference from man-made radio signals, which would easily overpower any of the signals the antenna was designed to pick up on.

“It is unlikely that we’ll be able to see any earlier into the history of stars in our lifetimes,” lead author Judd Bowman of ASU says. “This project shows that a promising new technique can work and has paved the way for decades of new astrophysical discoveries.”

It’s also the first actual glimpse we get into this period of the universe, a particularly important one — these were, after all, the universe’s early days. The foundation of everything we see today was laid down during that Epoch.

The paper, “An absorption profile centred at 78 megahertz in the sky-averaged spectrum” has been published in the journal Nature.

What is the Big Bang theory — how the Universe came to be

Have you ever wondered how our universe came to be? How does a universe come into existence?

You’d probably struggle to find a satisfying answer for that. Physicists all around the world had been bothered by this question for a long time, and the answer is still debatable. However, in their pursuit of fi, ding an answer they realized that space, time, energy and matter all came into existence at the birth of universe itself. So talking of a phase before that seemed as immaterial as “north of north pole”. Hence what initiated the universe or even what lies outside it is generally considered to be outside the remit of physics and more the concern of philosophy or metaphyhsics.

Therefore, physicists largely turned their focus on studying the evolution of universe. After years of research and experimentation, they came up with a beautiful theory to explain it. This was called The Big Bang Theory. But before looking into it, we need to know about an observation that decimated decades old notion of a static universe.

Our Universe is expanding

Just like Newton, Einstein believed that our universe is finite and static, or simply in a steady state. However, when he used his general theory of relativity to study the universe as a whole, he realized that space-time must be warped or curved around itself and hence due to the resulting gravitational pull it must be shrinking.

We don’t really know the shape of the Universe, but astrophysicists believe it’s one of these three shapes.

But he never quite came to terms with this idea. So he introduced a “cosmological constant” to maintain a static universe in his theory. Not everyone was a fan of this idea. Some scientists argued that introduction of this constant was completely arbitrary and was not backed up by any fact or observation.

Then in 1929, Edwin Hubble announced a dramatic discovery which completely stunned everyone.

While studying the light coming from other galaxies, he noticed that this light was shifted a little towards the red end of the spectrum due to Doppler Effect (also known as redshift) which indicated that galaxies were moving away from us. This observation was unchanged in every possible direction. In other words, the universe was expanding in all visible directions.

Now, if the galaxies were flying apart, then obviously at some time earlier, the universe would have been smaller than at present. So, tracing back the events just like a movie being played in reverse, we found that it was very tiny indeed.
Given the enormous scale of expansion of the universe, it was obvious that an equivalently enormous amount of energy must have liberated in the form of radiation. So it must be around today, and we might spot it. This speculation was accidentally confirmed by two young employees of Bell Telephone Laboratories in New Jersey. They picked up a mysterious microwave noise on their antenna which seemed to be coming equally from every direction in the sky. So eventually they realized that this microwave radiation must indeed be the “afterglow” of Big Bang.

The Big Bang theory

It is quite surprising to know that our seemingly endless universe was once smaller than the size of a proton. All the matter and energy was squeezes into an infinitesimally small volume. In fact, even the four fundamental forces of nature were coalesced together in this gravitational singularity. It is truly unfathomable to consider this much concentrated energy and matter, but all the evidence seems to support it.

Then at some point around 13.7 billion years ago, this singularity suddenly expanded to about 1026 times it’s original size in just 0.0001 seconds. This was what we call the Big Bang. The Big Bang theory is essentially a timeline of everything that happened thereon after.

Apart from the observations stated above the Big Bang model is also supported by two theories: General theory of relativity and the cosmological principle (the assumption that matter in the universe is uniformly distributed on large scales, i.e. the universe is homogeneous and isotropic).

Dark Energy and Gravity — the Yin and Yang of the Universe. Image credit: NASA/JPL-Caltech.

Although the rate of expansion of the universe has decreased ever since the cosmic inflation, presently the universe is expanding at an accelerated rate. This is a bit surprising considering the large amount of mass present in the universe which should have slowed down the expansion due to the gravitational pull. So the concept of antimatter was introduced in an attempt to explain that there is more to the universe than what we see. The anti matter acts opposite to the matter we know and hence it repels instead of attracting. The amount of anti matter being much greater than the total amount of matter the expansion of universe has accelerated.

So what’s next?

As of today we don’t seem to have the answer to “What the fate of universe will be”. But scientists generally agree that this fate will mainly depend on the universe’s overall geometry and the behavior of dark matter and dark energy on expansion of universe.

The universe could just stop expanding altogether reaching a state of maximum entropy and hence would become too cold to sustain life. Or it could continue expanding and lead to an event known as The Big Rip. Further advancements in fundamental physics are required before it will be possible to know the universe’s ultimate fate with a satisfying level of certainty.

 

New mathematical model analyzes early Universe

Swiss physicists have developed a new model to chart the early development of the Universe in better detail than ever before. Their code incorporates Einstein’s theory of general relativity as well as the existence of gravitational waves – which were just confirmed last week.

The Big Bang theory is the prevailing cosmological model for the universe from the earliest known periods. The model postulates that the universe expanded from a very high density and high temperature state, and it confirms and explains a series of observed phenomena – in other words, the observed data confirms the theory. But the timeline and early development universe still remains an area of hot debate, and this model could step in to answer some questions.

In the first phase, the very earliest universe was so hot, or energetic, that initially no matter particles existed or could exist perhaps only fleetingly. According to prevailing scientific theories, at this time the distinct forces we see around us today were joined in one unified force. The fact that we can even attempt to study, let alone model this early development is simply mind-blowing. The model is more accurate than all its predecessors, its creators say. It uses Einstein’s general relativity instead of Newton’s laws.

“This process is mainly governed by gravity, which is the dominant force on large scales,” the paper writes. “At present, a century after the formulation of general relativity, numerical codes for structure formation still employ Newton’s law of gravitation.”

The team from the University of Geneva analysed a cubic portion in space, consisting of 60 billion zones, each containing a particle (a portion of a galaxy). They modeled how all these particles move in relation to each other, plugging in data from Einstein’s equations, and using the UNIGE LATfield2 library.

“This conceptually clean approach is very general and can be applied to various settings where the Newtonian approximation fails or becomes inaccurate, ranging from simulations of models with dynamical dark energy or warm/hot dark matter to core collapse supernova explosions,” explains the new paper,published in the journal Nature Physics.

Their results are significant in more than one way. Directly, it puts a tangible size on the early universe, estimating the size of different early clusters. But on the other hand, this code will be made publicly available, so it could prove even more useful for people studying particular cosmological aspects – such as dark energy, which is estimated to make up 70% of the known universe. The code will also enable physicists to test the general theory of relativity on an unprecedented scale.

We’re zooming in to the birth of the Universe

water in early universe

Just one billion years following the Big Bang, water may had been as abundant as it is today

Water may have been plentiful in some parts of the universe as early as one billion years after the Big Bang, a new model suggests. That’s a lot earlier than scientists had previously presumed, seeing how at the very beginning the only elements were hydrogen and helium. Seeing how water is comprised of one oxygen atom (16 times heavier than hydrogen) and two hydrogen atoms, then we should have seen water much later, or so the thinking goes.

water in early universe

Image: DP Review

“We looked at the chemistry within young molecular clouds containing a thousand times less oxygen than our Sun. To our surprise, we found we can get as much water vapor as we see in our own galaxy,” says astrophysicist Avi Loeb of the Harvard-Smithsonian Center for Astrophysics (CfA).

The heavier elements were first forged in stars, which in their early days were mostly made of hydrogen and were very big. Inside these nurseries, heavier elements like carbon and good ol’ oxygen were forged, then scattered throughout the universe by stellar winds or nova events. Eventually the oxygen and hydrogen combine to form water, but only in reserved pockets around stellar hotspots. During these early days, however, these islands were much poorer in oxygen than gas within the Milky Way today.

This Hubble image features dark knots of gas and dust known as “Bok globules,” which are dense pockets in larger molecular clouds. Similar islands of material in the early universe could have held as much water vapor as we find in our galaxy today, despite containing a thousand times less oxygen. (Photo by NASA, ESA, and The Hubble Heritage Team)

This Hubble image features dark knots of gas and dust known as “Bok globules,” which are dense pockets in larger molecular clouds. Similar islands of material in the early universe could have held as much water vapor as we find in our galaxy today, despite containing a thousand times less oxygen. (Photo by NASA, ESA, and The Hubble Heritage Team)

The Harvard team wanted to find out just how much water could have been formed during those conditions in these molecular clouds. Taking into account that the universe was much hotter than it is today, temperatures around 80 degrees Fahrenheit (300 Kelvin), abundant water could form in the gas phase despite the relative lack of raw materials. Of course, being in close vicinity to stars means that water would often and regularly be broken down back to oxygen and hydrogen by nearby ultraviolet rays, but only to recombine again. This dance would have continued for some hundreds of millions of years until an equilibrium was reached.

“These temperatures are likely because the universe then was warmer than today and the gas was unable to cool effectively,” explains lead author and PhD student Shmuel Bialy of Tel Aviv University.

“The glow of the cosmic microwave background was hotter, and gas densities were higher,” adds Amiel Sternberg, a co-author from Tel Aviv University.

“You can build up significant quantities of water in the gas phase even without much enrichment in heavy elements,” adds Bialy.

Findings appeared in the journal  Astrophysical Journal Letters.

New study suggests Big Bang never occurred, Universe existed forever

Researchers have created a new model that applies our latest understanding of quantum mechanics to Einstein’s theory of general relativity and this is what they came up with – it’s truly hard to wrap your mind around that.

Currently accepted theories state that the Universe is around 13.8 billion years old, and before that everything in existence was squished into a tiny point – also known as the singularity – so incredibly compact that it contained everything that eventually became the Universe (actually, this is pretty hard to wrap your mind as well). As the Big Bang took place, the Universe started to expand, and it is expanding faster and faster to this day.

Image via AMNH.

The problem with current theories is that the math breaks down when you start to analyze what happened during or before the Big Bang.

“The Big Bang singularity is the most serious problem of general relativity because the laws of physics appear to break down there,” co-creator of the new model, Ahmed Farag Ali from Benha University and the Zewail City of Science and Technology, both in Egypt, told Lisa Zyga from Phys.org.

Working in a team which included Sauya Das at the University of Lethbridge in Alberta, he managed to create a new satisfying model in which the Big Bang never occurred, and the Universe simply existed forever.

“In cosmological terms, the scientists explain that the quantum corrections can be thought of as a cosmological constant term (without the need for dark energy) and a radiation term. These terms keep the Universe at a finite size, and therefore give it an infinite age. The terms also make predictions that agree closely with current observations of the cosmological constant and density of the Universe.”

According to this model, the Universe also has no end, which is perhaps even more interesting if you think about it, and that it is filled with a quantum fluid, which might be composed of gravitons – hypothetical particles that have no mass and mediate the force of gravity.

The model shows great promise, but it has to be said – it’s only a mathematical theory at this point. We don’t have the physics to back it up or prove it wrong at the moment, and we likely won’t have it in the near future. Still, it’s remarkable that it solves so many problems at once, and the conclusions are very intriguing.

“It is satisfying to note that such straightforward corrections can potentially resolve so many issues at once,” Das told Zyga.

Read the full study here.

BICEP2 (in the foreground) and the South Pole Telescope (in the background). Credit: Steffen Richter, Harvard University

Gravity waves laid to dust: when scientists get way ahead of themselves

BICEP2 (in the foreground) and the South Pole Telescope (in the background). Credit: Steffen Richter, Harvard University

BICEP2 (in the foreground) and the South Pole Telescope (in the background). Credit: Steffen Richter, Harvard University

Nobel prizes, international press coverage, awards – these were all promises and cheers thrown about all over the web after a team of physicists trumpeted during a conference at Harvard that they’ve made one of the biggest discoveries in science: gravity waves. Some theories claim that these waves were generated brief moments following the Big Bang, and a team of researchers based at the  BICEP2 facility in Antarctica claimed during the aforementioned press conference in March that they’ve finally confirmed the models and have discovered evidence that support gravitational waves. A week ago, however, scientists from another team that works with the Planck satellite made its own measurements and came to an entirely difference conclusion. What BICEP2 detected weren’t gravity waves at all, but polarized light produced by specks of dust in the galaxy.

“Extraordinary claims require extraordinary evidence”

No problem, the BICEP2 was proven wrong. That’s how science works, fortunately – one scientist or group reports a result (revolutionary or not), then another group replicates the results to confirm or not the findings. Science prides itself on contradictions, because that’s how the veil of confusion is ultimately lift to reveal truth. The problem is that the BICEP2 team behaved unscientific by announcing their results before these were verified by anyone outside the group. I’m not out to criticize them personally, I’m just trying to signal that this very event is an example of what can go wrong (hint: everything) went scientists steer away from a basic pillar that’s been proven time and time again to work: peer review. It’s not like this is the first time something like this happens. Only a couple of years ago a team at CERN made a most audacious claim that neutrinos could travel faster than light. The claim was later refuted and the initial results were attributed to some bad wiring in the detection tech. Some scientists from the project resigned, lives may have been ruined. Once again, we return to the basics : extraordinary claims require extraordinary evidence.

Video showing one of BICEP2’s researchers at Andrei Linde’s doorstep to celebrate. Linde is one of the theorists whose work they claimed to have proved.

Both the Planck satellite and the South Polar BICEP2 telescope are designed to study what’s called the cosmic microwave background (CMB). First discovered in 1964 in a groundbreaking paper, CMB can be liken to fossil light waves that are rippling through space to this day after being emitted some 300,000 years following the Big Bang. Since their discovery 50 years ago, the CMB has been the go to source for studying cosmological phenomena. Like CMB, gravity waves are also relics from a time long past, only these are theorized to have been emitted only fractions of a second after the Big Bang. By probing gravity waves, physics would be able to tell a great deal about what was going on in those critical moments that spurred the cosmic inflation. Most notably, it would help scientists differentiate between the so many cosmic inflation theories proposed until today.

After carefully analyzing their own observations for the cosmic microwave background, the Planck team concluded that the supposed signal for gravity waves was, more likely, just emission from dust. To analyze cosmic background radiation, scientists need to first subtract the glow of our own galaxy in the same wavelengths as the CMB microwaves. Apparently, the BICEP2 experiment missed to include maps of the dust polarisation from the Milky Way in their calculations (they didn’t have them at their disposal, granted). In the end, the researchers underestimated the foreground emission from dust, and therefore over-estimated the significance of any claimed gravitational wave detection.

Some people said this event gives science a bad rep. We’re all flooded with misinterpreted, out of context news that herald all sorts of scientific developments that turn out to be otherwise in reality. This time, it wasn’t the press that blew it; it was the scientists.

 

grav waves

First direct evidence supporting the “Cosmic Inflation” theory helps explains how the Universe came to be

The BICEP2 experiment at the South Pole reported the first ever piece of evidence that support the cosmic inflation theory of how the universe cam to be. Their data suggests that scientists have come across signals left over by the super-rapid expansion of space that must have occurred just fractions of a second after everything came into being. Nothing short of extraordinary, the findings will be under intense peer-review scrutiny in the coming months and if indeed found valid by the rest of the scientific community on Earth, this would make it on of the most important discoveries in science.

The confirmation of the Higgs boson – the elementary subparticle that grants fundamental particles mass – was monumental. Now, only a year after its confirmation, the world of physics has a new hallmark discovery that warrants its attention – one that yet again shows that science is on the brink of entering a realm of ‘new’ physics, as some describe.

Some 13.8 billion years ago, the Universe came to existence in a Big Bang. This, at least, is known by most of us, but for scientists researching the genesis of the universe there are still some loose ends. Simply put, many explanations that speculate what the first absolute moments following this cosmic inception looked like are just theories, with little or no tantalizing evidence supporting it. The cosmic inflation theory was first proposed in the 1980s by physicist Alan Guth as a modification to the conventional Big Bang theory. It envisions the formation of the Universe not as a rapidly expanding fireball, instead the universe inflated extremely rapidly from a tiny piece of space and became exponentially larger in a fraction of a second. This idea immediately attracted lots of attention because it could provide a unique solution to many difficult problems of the standard Big Bang theory. As an analogy, the theory holds that in the universe’s very first first trillionth, of a trillionth of a trillionth of a second would have taken something unimaginably small to something about the size of a marble.

An inflating Universe

The BICEP2 telescope is located on the South Pole, where practically you’re the closest you can be to space and still be on the ground. This makes it an ideal place for ground-based observations, in addition to the  cold, dry, stable air, which allows for crisp detection of faint cosmic light. The experiment’s main purpose is that of peering through the cosmic microwave background which looms through the whole Universe since the Big Bang. Scientists consider this cosmic background as a form of light since it exhibits all the properties of light, including polarization. While on Earth, polarization of light is caused by the atmosphere which scatters incoming photons, in the case of cosmic radiation, the ‘light’ is scattered by the various atoms and electrons it comes into contact with.

“Our team hunted for a special type of polarization called ‘B-modes,’ which represents a twisting or ‘curl’ pattern in the polarized orientations of the ancient light,” said BICEP2 co-leader Jamie Bock, a professor of physics at Caltech and NASA’s Jet Propulsion Laboratory (JPL).

grav waves

With much consideration, researchers at the telescope discovered this distinct mode of polarization, which was anticipated by the inflation theory. Namely, the theory followed that cosmic inflation should have been associated with waves of gravitational energy – rippled in the fabric of space that leave tantalizing marks on the cosmic background radiation. Not only this, the signal was reported as being very strong, which makes measurement errors less likely and, at the same time, discredits other theories which predict low signals. The results also constrain the energies involved – at 10,000 trillion gigaelectronvolts. This is consistent with ideas for what is termed Grand Unified Theory, the realm where particle physicists believe three of the four fundamental forces in nature can be tied together.

“This has been like looking for a needle in a haystack, but instead we found a crowbar,” said co-leader Clem Pryke, an associate professor of physics and astronomy at the University of Minnesota.

This is an extraordinary find, but yet it still a claim – not yet confirmed – and like we know, extraordinary claims, require extraordinary evidence. With this in mind, the reputed researchers spent three years carefully shifting through data, tying loose ends and making sure what they found wasn’t a fluke, just some mistake. The scientists did their best, and as far as they’re concerned, they couldn’t find anything that would contradict their measurements and readings. There will be others now that will need to review this work, putting their heads together to find flaws in the research. If deemed fit, well ready that Nobel!

“I can’t tell you how exciting this is,” said Dr Jo Dunkley, who has been searching through data from the European Planck space telescopefor a B-mode signal.

“Inflation sounds like a crazy idea, but everything that is important, everything we see today – the galaxies, the stars, the planets – was imprinted at that moment, in less than a trillionth of a second. If this is confirmed, it’s huge.”

Technical details and journal papers can be found on the BICEP2 release website: http://bicepkeck.org

So, what does Dr. Linde has to say about all this? His reaction is priceless!

Scientists reproduce conditions from early universe

Physicists have successfully reproduced a pattern resembling the cosmic microwave background radiation in an experiment which used ultracold cesium atoms in a vacuum chamber. This is the first experiment which recreates at least some of the conditions from the Big Bang.

“This is the first time an experiment like this has simulated the evolution of structure in the early universe,” said Cheng Chin, professor in physics. Chin and his associates reported their feat in the Aug. 1 edition of Science Express, and it will appear soon in the print edition of Science.

universe big bang

The cosmic microwave background radiation (CMB or CMBR) is basically the thermal radiation left over from the Big Bang. It is very interesting for astrophyicists because it apparently exhibits a large degree of uniformity throughout the entire universe (it has more or less the same values everywhere you look for it). If you analyze the “void” between stars and even galaxies with a sufficiently sensitive radio telescope, you’ll see a faint background glow, almost exactly the same in all directions, that is not associated with … anything. The glow has the most energy in the microwave spectrum. Its rather serendipitous discovery took place in 1964, and it earned its finders a Nobel prize in 1978.

You can think of this radiation as the echo of the Big Bang – by studying it, we get a somewhat clear idea how the Universe looked some 380,000 years following its ‘birth’ – incredibly early; it doesn’t go much before or after, it’s basically a snapshot of the past. But as it turns out, under certain conditions, a cloud of atoms chilled to a billionth of a degree above absolute zero in a vacuum chamber displays phenomena similar to those which followed the big bang.

“At this ultracold temperature, atoms get excited collectively. They act as if they are sound waves in air,” he said.

This neatly correlates with what cosmologists speculated:

“Inflation set out the initial conditions for the early universe to create similar sound waves in the cosmic fluid formed by matter and radiation,” Hung said.

big bang

The tiny universe which was simulated in Chin’s laboratory measured no more than 70 microns across (about as big as a human hair) – but the physics is the same regardless of the size of your universe.

“It turns out the same kind of physics can happen on vastly different length scales,” Chin explained. “That’s the power of physics.”

But there is an important difference – and one that works greatly to our advantage:

“It took the whole universe about 380,000 years to evolve into the CMB spectrum we’re looking at now,” Chin said. But the physicists were able to reproduce much the same pattern in approximately 10 milliseconds in their experiment. “That suggests why the simulation based on cold atoms can be a powerful tool,” Chin said.

If you want, you can think of the Big Bang in oversimplified terms as an explosion which made a big BOOM! These sound waves began interfering with each other creating complicated patterns – the so-called Sakharov acoustic oscillations.

“That’s the origin of complexity we see in the universe,” he said.

This is indeed a powerful tool to find out more about our infant universe, but this is just the first step. Chin and his team plan to move on to use these Sakharov oscillations to study the property of this two-dimensional superfluid at different initial conditions, then cross check their results with what is observed by cosmologists. They will use the same type of experiment but branch out to other fields of cosmology, including the formation of galaxies and even black hole dynamics.

“We can potentially use atoms to simulate and better understand many interesting phenomena in nature,” Chin said. “Atoms to us can be anything you want them to be.”

Interestingly enough, nobody on this team was a cosmologist.

Journal Reference: C.-L. Hung, V. Gurarie, C. Chin. From Cosmology to Cold Atoms: Observation of Sakharov Oscillations in a Quenched Atomic Superfluid. DOI: 10.1126/science.1237557

The current accept cosmological model of the formation of the Universe states that it is expanding ever since the Big Bang. It's easy to envision this like a balloon inflating: each point on the balloon is drifting away relative to each other point on the balloon as it inflates, so there is no center of the Universe. (c) TAKE 27 LTD/SPL

New cosmology model claims Universe may not be expanding

The current accept cosmological model of the formation of the Universe states that it is expanding ever since the Big Bang. It's easy to envision this like a balloon inflating: each point on the balloon is drifting away relative to each other point on the balloon as it inflates, so there is no center of the Universe. (c) TAKE 27 LTD/SPL

The current accepted cosmological model of the formation of the Universe states that it is expanding ever since the Big Bang. It’s easy to envision this like a balloon inflating: each point on the balloon is drifting away relative to each other point on the balloon as it inflates, so there is no center of the Universe. (c) TAKE 27 LTD/SPL

Physicists today and the theories they currently elaborate are seemingly entrenched in one major idea: that the Big Bang occurred once in a moment of singularity (infinitely dense Universe) and has expanded ever since. Christof Wetterich, a theoretical physicist at the University of Heidelberg in Germany, has an alternate view. He believes the Universe is not expanding, and that all particles in the Universe are increasing in mass, which would explain why galaxies are shifting away from us.

To tell if an object is moving towards or away from Earth, astronomers study the light emitted by these objects. This light has a characteristic frequency (color), depending on the object itself and what gets absorbed or not. When matter is moving away from us, these frequencies appear shifted towards the red, or lower-frequency, part of the spectrum (redshift), and when matter is moving towards us, these frequencies are shifted towards the blue, higher-frequency, part of the spectrum (blueshift). This is called the Doppler effect, and we all experience it each day (i.e. the sound a car makes when it rushes towards us is lower pitched than the sound the car makes after it drives past us).

In the 1920s, Georges Lemaître and Edwin Hubble found that the light emitted by galaxies was red-shifted, which later helped them elaborate a landmark paper in cosmology today that claimed the Universe is expanding. The characteristics of light, however, are also governed by mass.  If an atom were to grow in mass, the photons it emits would become more energetic. Because higher energies correspond to higher frequencies, the emission and absorption frequencies would move towards the blue part of the spectrum. Conversely, if the particles were to become lighter, the frequencies would become redshifted.

The Universe isn’t expanding, it’s just gaining mass

Here’s where Wetterich idea becomes interesting. Einstein’s Theory of Special Relativity states that the speed of light is finite and that nothing can travel at a higher velocity than it. This means that the light we’re seeing or receiving from distant objects is like a history book or better yet a form of time capsule – we can only see it as it would have been at the time of emission. Sometimes, light can take billions of years to reach us and in the meantime the object that emitted the light might no longer exist today, for instance.

If all masses were once lower, and had been constantly increasing, the colours of old galaxies would look redshifted in comparison to current frequencies, and the amount of redshift would be proportionate to their distances from Earth. Thus, the redshift would make galaxies seem to be receding even if they were not.

With this in mind, if we were to consider that the mass of all  matter is constantly increasing, after doing the math we get that the Universe still expands rapidly, but only during a short-lived period known as inflation. But prior to inflation, according to Wetterich, the Big Bang no longer contains a ‘singularity’ where the density of the Universe would be infinite, and which has been giving physicists headaches for years trying to make sense of an event where the General Theory of Relativity doesn’t stand anymore. In Wetterich’s model, the Big Bang stretches out in the past over an essentially infinite period of time, meaning the cosmos could be static, or even beginning to contract. Newton would had been pleased.

We’ll never know for sure if this theory is right

There’s one big problem with this theory though, despite no physicist has yet to refute it as totally implausible yet – it can not be tested. Mass is what’s known as a dimensional quantity, and can be measured only relative to something else. For instance, every mass on Earth is ultimately determined relative to a kilogram standard that sits in a vault on the outskirts of Paris, at the International Bureau of Weights and Measures. If the mass of everything — including the official kilogramme — has been growing proportionally over time, there could be no way to find out.

Nevertheless, the theory still remains very fascinating and for one it offers an alternate cosmological model where no singularity exists, which would come at a significant advantage. If anything else, though, the theory remains valuable in itself since it offers an alternate picture of our Universe, one that might stir other physicists to think outside the box a bit and challenge our current accept cosmological Big Bang centered model. After all, it’s still just a theory. It would be really disappointing if it were wrong and we all concentrated our efforts modeling the world around it.

Wetterich’s paper was published on the arXiv preprint server. [source: Nature]

Quantum theory takes out singularity, suggests black holes are wormholes

Black holes are the single most interesting and puzzling objects in our Universe – that we know of. But as if they weren’t mysterious enough, researchers have found that if you apply a quantum theory of gravity to these bizarre objects, the all-crushing singularity at their core disappears, opening a whole new Universe of possibilities – literally.

What we know so far

black hole singularityAt the center of every black hole, there lies what is called a singularity – a region where space and time becomes inifinite – this was described by Albert Einstein. If you get sucked into singularity, you will become inifitely dense, but what happens after that… nobody really knows. From a mathematically physical point of view, nothing happens from that point on.

“When you reach the singularity in general relativity, physics just stops, the equations break down,” says Abhay Ashtekar of Pennsylvania State University.

But this isn’t a problem limited strictly to black holes – the big bang, the one birth of our universe is thought to have  also started out with a singularity – a singularity which again, breaks the limits of general relativity.

Adding a little quantum physics

bounce

As if things weren’t strange enough already, researchers started to add quantum physics in the mix: in 2006, Ashtekar and colleagues applied loop quantum gravity (LQG) to the birth of the universe.

LQG combines general relativity with quantum mechanics and defines space-time as a web of indivisible chunks of about 10-35 metres in size. What they found was absolutely stunning: as they went back in time in an LQG Universe, they reached the big bang, but no singularity – instead, something even more curious happened: they crossed a “quantum bridge” (politically correct term for a wormhole) into another older universe, basically confirming the Big Bounce Universe theory.

The Big Bounce is a hypothetical scientific model that claims all Universal start and end is cyclic – every Big Bang is the result of the collapse of a previous Universe.

Again, this happened in 2006, and now, Jorge Pullin at Louisiana State University and Rodolfo Gambini at the University of the Republic in Montevideo, Uruguay, have applied LQG on a much smaller scale: to an individual black hole – results were, again, stunning.

Wormholes and quantum physics

 

wormholeIn this new model, gravitational field still increased, but it didn’t reached singularity, and after you’ve passed the black hole’s center, tha gravity starts dropping, and as you come out on the other side (assuming that could be possible), you would end up in another region of our universe, or another universe altogether. Despite only holding for a simple model of a black hole, the researchers – and Ashtekar – believe the theory may banish singularities from real black holes too.

So there is a mathematical theory which suggests that if you go on one end of a black hole, you will end up in another part of the Universe, or in another Universe alltogether. While other theories, not to mention some works of science fiction, have suggested this – now it’s real business. But here’s the kicker:

It is now believed that black holes are also supposed to evaporate over time. As they soak up matter and information over a long period of time, if the information ends up in another Universe, then from our point of view, the information would be gone forever – practically destroyed – and that defies quantum theory itself!

But researchers suggest that if the black hole has no singularity, then the information needn’t be lost – it may just tunnel its way through to another universe – and we have to take that into consideration as well.

“Information doesn’t disappear, it leaks out,” says Pullin.

Sometimes, it just feels that life would be much simpler without quantum physics.

Journal Reference: Loop Quantization of the Schwarzschild Black Hole

hawking

The Big Bang didn’t need God to happen, says Stephen Hawking @ Caltech. Also, dark matter discovery seen as most immediate goal

hawkingRenowned physicist, famous for his study of black holes, galaxies and for authoring a popular book on the origin of the universe, “A Brief History of Time”, recently arrived at Caltech, like every year, where he held a talk in front of 1,000 people who had waited in line for 12 hours to hear him speak. Hawking’s talk, as always, encompassed discussions pertaining to questions like “why are we here?” , “how did the universe came to be?” and such.

Hawking began his talk with  an African creation myth, but didn’t stray too far from his theological intro. The physicist noted, possibly in irritation, how some people seeking to find a divine solution to the creation of the Universe prefer to  counter the theories of curious physicists with poor arguments. Rather rash or not, he said “What was God doing before the divine creation? Was he preparing hell for people who asked such questions?”

As you can imagine, this stirred a few people in the audience and many more hearing about it on the web. People should have gotten used to this, however. The pope himself picked on Hawking on several occasions for his alleged disdainful claims against god. A few years ago, I wrote a piece on ZME where I also quoted some of Hawking’s answers to questions pertaining to divinity, like the afterlife. Back then, he asserted there is no heaven, nor hell, but nothingness.

How did the Universe came to be? What triggered the Big Bang? Hawking’s talk continued on with discussions relating to various creation theories some still standing, other long debunked by recent findings made possible with modern space telescopes. One of these debunked theories is  Fred Hoyle and Thomas Gold’s steady-state theory which held that there isn’t actually a head and a tail to all of this and that space bodies like galaxies, the stars that comprise them are made out of spontaneously formed matter.

Hawking also says that the Big Bang occurred at a moment of singularity, as  he and physicist Roger Penrose proved in the 1980s the universe could not “bounce” when it contracted, as had been theorized, and that most likely the Big Bang happened only once. Recent refined measurements that position the Universe’s age at roughly 13.8 billion years are on par with Hawking’s model. Still, what would be a valid theory for the Universe’s inception according to Hawking? He believes the “M-theory”, a hypothesis that is based on ideas first moved forward by lifelong Caltech lecturer Richar Feynman, as the single most valid model he has currently encountered that can explain what he has observed. In fine line, the theory – an extension to string theory – states multiple universes are formed out of nothing. Only a few are capable of creating conditions for supporting life, and even much fewer conditions for intelligent life similar to humans.

Dark matter‘s discovery, which along with dark energy combine to amount to 95% of all matter making the normal matter that can be seen and observed only 5%, is seen by Hawking as the next barrier physics needs to breach. After understanding the nature of dark matter and dark energy, many of today’s missing links could be put together and physicists may finally be able to paint an accurate picture of cosmos. Dark energy, physicists believe, would explain why the universe is expanding at an ever-growing rate instead of collapsing under its own gravity.

“There have been searches for dark matter, but so far no results,” he said. We presume, however, that he is up to date with recent reports from experiments both in space and undergrounds labs where hints suggesting the detection of dark matter have been sighted.

Hawking has been living dreadful disease – Lou Gherig’s disease – for the past 50 years which has deteriorated his motor neurons leaving him unable to move his limbs or any body part for that matter. At the time of his diagnosis he was told he would live for only two more years.

Scientists create a remix of the Big Bang sound

A decade ago, American physics professor John Cramer released an audio file which made history: the sound of the theorized Big Bang that formed the universe. Now, armed with new data and more observations, Cramer has released a remix – an improved version of the universe’s first one hit wonder.

“In general, there are no sounds in space, because there is no air to vibrate,” Cramer, a professor emeritus at the University of Washington, tells QMI Agency.

However, during the Big Bang, the universe was an inimaginably different place.

“The Big Bang is the exception to this, because the medium that pervaded the universe in the first 100,000 years or so was far more dense than the atmosphere of the Earth.”

So what he did was to trace compression waves (sound waves) like ripples in a pool or the ringing of a bell to their source.

“The initial sound waves left a “fingerprint” on the cosmic microwave background in the form of temperature variations,” he explains. “If you were there then, you might hear something like the bottled sound, but the frequencies present then would be very much lower than the simulation.”

Cosmic microwave background seen by Planck

Map of the earliest recorded light paints broad picture of the ancient Universe

Cosmic microwave background seen by Planck

Cosmic microwave background seen by Planck. (c) ESA

Using the incredible  Planck cosmology probe astronomers at the European Space Agency have assembled a map of the “oldest light” in the sky – the cosmic microwave background (CMB) that was thrown into space in all directions just a few hundred thousand years after the Big Bang and which is still picked up here on Earth today.

What’s exciting about the map is that it confirms the current fundamental “cosmological inception” theory – the Big Bang theory. However there are some features and ideas that need to be refined and rethought as a result of the findings. For instance, according tot the new Planck all-sky map, the Universe is  13.82 billion years or 50 million years older than previous estimates. Also, there seems to be more matter (31.7%) and slightly less “dark energy” (68.3%) – the mysterious force that drives the Universe apart and causes an accelerated expansion.

The trace the map, cosmologists studied the CMB – light that was allowed to escape after the early Universe cooled down to allow the formation of hydrogen atoms some 380,000 years ago. By studying temperature fluctuations of the CMB –  seen as mottling in the map – scientists can better assess their current theoretical models with actual data on anomalies, since these fluctuations are thought to actually  reflect the differences in the density of matter when the light first escaped. These ripples are thought to have given rise to today’s vast cosmic web of galaxy clusters and dark matter.

anomaliesWhile some statistical analysis isn’t on par with data provided by the Planck map, cosmologists should rejoice as the news that their fundamental theories reflect reality. Especially those relating to the birth of the Universe, which is thought to have started as hot, dense state in an incredibly small space, and then expanded and cooled.

A cosmic baby picture

Other projects like the Cosmic Background Explorer and the Wilkinson Microwave Anisotropy Probe have provided earlier drafts of the “baby Universe”, however the map obtained from data gathered by the $900 million (€700 million) Planck probe launched in 2009 is the most detailed yet.

“The extraordinary quality of Planck’s portrait of the infant Universe allows us to peel back its layers to the very foundations, revealing that our blueprint of the cosmos is far from complete. Such discoveries were made possible by the unique technologies developed for that purpose by European industry,” says Jean-Jacques Dordain, ESA’s Director General.

“Since the release of Planck’s first all-sky image in 2010, we have been carefully extracting and analysing all of the foreground emissions that lie between us and the Universe’s first light, revealing the cosmic microwave background in the greatest detail yet,” adds George Efstathiou of the University of Cambridge, UK.

What also came as a surprise was a rather discrepant anomaly. Apparently, there’s an asymmetry in average temperature distribution across the Universe, as the southern sky hemisphere is slightly warmer than the north. Another significant anomaly is a cold spot in the map, centred on the constellation Eridanus, which is much bigger than would be predicted.

Nevertheless, cosmologists which have been dreaming about such a map for decades will now have their work cut out for them. Armed with this map, they now have the necessary resources or at least another tool at hand to prove or disprove some of the most controversial theories in cosmology today, like those discussing the rapid and far-reaching inflation of the Universe in its first moments from inception or the claim that there are six or seven spatial dimensions in addition to the three we perceive.

source: ESA

The inset at left shows a close-up of the young dwarf galaxy. This image is a composite taken with Hubble's WFC 3 and ACS. Credit: NASA, ESA, and M. Postman and D. Coe (STScI) and CLASH Team.

Farthest known object in the Universe is 13.3 billion years old

The inset at left shows a close-up of the young dwarf galaxy. This image is a composite taken with Hubble's WFC 3 and ACS. Credit: NASA, ESA, and M. Postman and D. Coe (STScI) and CLASH Team.

The inset at left shows a close-up of the young dwarf galaxy. This image is a composite taken with Hubble’s WFC 3 and ACS. Credit: NASA, ESA, and M. Postman and D. Coe (STScI) and CLASH Team.

NASA scientists have announced they have discovered the farthest object discovered so far in the Universe, a 13.3 billion old galaxy or a mere 420 million years after the Big Bang.

That’s not to say that its 13.3 billion light years away from Earth, since the Universe has expanded greatly since then and the actual distance might be much greater than this figure. It means that light took 13.3 billion years to reach us.

The galaxy has been dubbed  MACS0647-JD and was discovered using a combination of NASA’s Hubble and Spitzer space telescopes, along with gravitational lensing – an interstellar technique that uses distant galaxies to create a zooming effect for the light that passes through them. Without gravitational lensing, this discovery would have been impossible with the current technology employed in telescopes.

“This [magnification galaxy] does what no manmade telescope can do,” Marc Postman, of Baltimore’s Space Telescope Institute, said in a release. “Without the magnification, it would require a Herculean effort to observe this galaxy.”

Essentially, the scientists have looked into the past – 13.3 billion years into the past. What they saw was a galaxy that was only a tiny fraction of the Milky Way. More exactly, it’s been estimated as being only 600 light years wide. For compassion, the Large Magellanic Cloud, a dwarf galaxy companion to the Milky Way, is 14,000 light-years wide. Our Milky Way is 150,000 light-years across.

Since then it has most likely grown, and even collided already with other galaxies. The previous record holder was a gamma ray burst just 600 million years after the Big Bang.

“Over the next 13 billion years, it may have dozens, hundreds, or even thousands of merging events with other galaxies and galaxy fragments,” Dan Coe, lead author of the study announcing the discovery, said in a release. “This object may be one of many building blocks of a galaxy.”

source: NASA

Faint galaxy sheds light on the dawn of the Universe – many more to be found

The first galaxies formed very fast after the Big Bang – in cosmic time, that is. It’s estimated that the earliest ones appeared some 500 million years after the Big Bang, a period about which researchers know very little.

How they observed it

Source: The CLASH team/Space Telescope Science Institute

Even though they are typically very bright, such galaxies are quite hard to observe because they are very far away and only a small fraction of their light can make its way towards Earth, a fraction so small it’s almost impossible to pick up. However, the Hubble telescope managed to detect light from a small galaxy emitted just 500 million years post-Big Bang, a period when the Universe was still in its infancy.

The telescope was able to do this thanks to a phenomena called gravitational lensing: basically, when you have an observe (Hubble), a distant source (the galaxy) and a certain distribution of matter (a galaxy cluster for example), the light emitted by the source can be bent and the observer can observe it easier; gravitational lensing is one of the predictions involved by Einstein‘s general theory of relativity. Basically, the massive gravity of the galaxy cluster acts just like a lens.

In this case, astronomer Wei Zheng and colleagues using the Hubble and Spitzer Space Telescopes reported light was magnified 15 times, making it just strong enough to be observed. Even so, the galaxy MACS 1149-JD appeared as a mere blob, and only after repeated measurements were they able to conclude that it is most likely a galaxy.

How they know its age

The Universe is expanding; galaxies produce light with specific spectral properties, based on the stars and gas they contain. Combine these two facts, and you can understand that light emitted by early galaxies was stretched shifting the entire spectrum into a different wavelength range, a phenomenon called cosmic redshift. All electromagnetic types of radiation (light included) have an electromagnetic spectrum – the range of all possible frequencies of electromagnetic radiation. Cosmic redshift means light seen coming from an object that is moving away is proportionally increased in wavelength, or shifted to the red end of the spectrum.

So, using multiple measurements from the Spitzer and Hubble telescope, they estimated that the light was emitted 490-505 million years after the Big Bang. But their conclusions are perhaps even more interesting. Instead of suggesting MACS 1149-JD is a special snowflake, astronomers believe there are many more such galaxies, formed in the same era, the ‘first’ era, just waiting to be discovered.

Scientific article was published in Nature

Glow harbors first objects in the universe. infrared imaged by Spitzer Space Telescope

Ethereal glow might harbor the Universe’s first objects

Glow harbors first objects in the universe. infrared imaged by Spitzer Space Telescope

First discovered in 2005, and then studied in more depth since 2007, NASA scientists have finally isolated the ethereal glow thought to originate from the very first objects in the Universe with the highest precision yet.

As seen in the image above, depicted in orange and red, the ‘lumpy’ infrared glow was observed using the ever faithful Spitzer Space Telescope, a remarkable device which has so far delivered numerous valuable scientific data about the cosmos. The scientists suggest the glow was given off by wildly massive stars or voracious black holes. The exact source can not be pinpointed with the available technology today, but what seems rather certain is that it originated from the very first objects in the Universe 13 billion years ago, shortly, in cosmic time that is, after the “Big Bang“, which is theorized to had occurred 13.7 billion years ago.

“All we can say is that these sources do not exist among the known galaxy populations, which have been observed to very early times (large distances),” said Alexander “Sasha” Kashlinsky, a NASA scientist who led the team that made the discovery. “This likely puts us within the first half-giga-year of the universe’s evolution, the epoch of first stars.”

The intriguing glow, known as cosmic infrared background, was first sighted by Spitzer in 2005, but only in recent years was the telescope able to isolate it. Scientists directed Spitzer at a region of interest in the sky — near the constellation Boötes — and studied it for over 400 hours, after which they carefully subtracted all of the known stars and galaxies in the images.

What remained were faint patterns of light with several telltale characteristics of the cosmic infrared background.

“These objects would have been tremendously bright,” says Alexander Kashlinsky of NASA’s Goddard Space Flight Center.

“We can’t yet directly rule out mysterious sources for this light that could be coming from our nearby universe, but it is now becoming increasingly likely that we are catching a glimpse of an ancient epoch. Spitzer is laying down a roadmap for NASA’s upcoming James Webb Telescope, which will tell us exactly what and where these first objects were.”

Their first light would have originated at visible or even ultraviolet wavelengths and then, because of the expansion of the universe, stretched out to the longer, infrared wavelengths observed by Spitzer. The telescope, however, has a short-wavelength view and thus can not answer unambiguously whether these objects were stars, black holes, galaxies or some previously unknown celestial formation. The new study measures this cosmic infrared background out to scales equivalent to two full moons – significantly larger than before. They plan to explore more patches of sky in the future.

“We hope to achieve this in the coming years (or months),” Kashlinsky said.

Such investigations would have access to a broader picture, and thus answers as well, once with the deployment of the highly anticipated James Webb Space Telescope, slated for launch in 2018. The James Webb Telescope is a massive, cutting-edge space telescope designed to orbit 1 million miles from Earth, where it would observe the mid-infrared portion of the electromagnetic spectrum. This would make it capable of gazing through some of the earliest forms of the Universe.

“This is one of the reason’s we are building the James Webb Space Telescope,” says Glenn Wahlgren, Spitzer program scientist. “Spitzer is giving us tantalizing clues, but James Webb will tell us what really lies at the era where stars first ignited.”

The findings were reported in the journal The Astrophysical Journal.

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