What triggered the Big Bang?
Some speculative proposals in this regard, each of which entails untested hypotheses, are:
- The simplest models, in which the Big Bang was caused by quantum fluctuations. ...
- Models in which the whole of spacetime is finite, including the Hartle–Hawking no-boundary condition. ...
- Brane cosmology models, in which inflation is due to the movement of branes in string theory; the pre-Big Bang model; the ekpyrotic model, in which the Big Bang is the ...
What evidence supports the Big Bang theory?
There are several pieces of evidence that support the Big Bang Theory. These are the following: Most of the galaxies appear red shifted, an indication that they are moving away from us and that the universe is expanding.
Was the Big Bang real?
The big bang is obviously real due to scientists seeing that distant galaxies are further red-shifted from spectrography. This shows that the universe must be expanding and, therefore, it evidences that at one point the universe must have started as a singularity - when the big bang took place (huge burst of gamma rays which can also be detected as CMBR today).
What is the meaning of the Big Bang theory?
The Short Answer: The big bang is how astronomers explain the way the universe began. It is the idea that the universe began as just a single point, then expanded and stretched to grow as large as it is right now—and it is still stretching! What's This Big Bang All About? In 1927, an astronomer named Georges Lemaître had a big idea.
What was the origin of the Big Bang?
Like most stories in science, the origin of the Big Bang has its roots in both theoretical and experimental/observational realms. On the theory side, Einstein put forth his general theory of relativity in 1915: a novel theory of gravity that sought to overthrow Newton’s theory of universal gravitation. Although Einstein’s theory was far more intricate and complicated, it wasn’t long before the first exact solutions were found.
What does the Big Bang teach us?
The Big Bang teaches us that our expanding, cooling universe used to be younger, denser, and hotter in the past.
What do the blue and red lines mean in the Big Bang?
Blue and red lines represent a “traditional” Big Bang scenario, where everything starts at time t=0, including spacetime itself. But in an inflationary scenario (yellow), we never reach a singularity, where space goes to a singular state; instead, it can only get arbitrarily small in the past, while time continues to go backwards forever. Only the last minuscule fraction of a second, from the end of inflation, imprints itself on our observable universe today. (Credit: E. Siegel)
How many fronts does inflation have?
On those four fronts, inflation is 4-for-4, while the hot Big Bang is 0-for-4.
What would happen if the universe had a higher density?
If the universe had just a slightly higher density (red), it would have recollapsed already ; if it had just a slightly lower density, it would have expanded much faster and become much larger. The Big Bang, on its own, offers no explanation as to why the initial expansion rate at the moment of the universe’s birth balances the total energy density so perfectly, leaving no room for spatial curvature at all. ( Credit: Ned Wright’s cosmology tutorial)
Is the Big Bang correct?
First, the original notion of the hot Big Bang, where the universe emerged from an infinitely hot, dense, and small singularity — and has been expanding and cooling, full of matter and radiation ever since — is incorrect. The picture is still largely correct, but there’s a cutoff to how far back in time we can extrapolate it.
Does inflation reproduce the success of the Big Bang?
Inflation reproduces all of the successes of the hot Big Bang; there’s nothing that the hot Big Bang accounts for that inflation can’t also account for.
What is the Big Bang?
More specifically, the Big Bang can also refer to the birth of the observable universe itself — the moment something changed, kickstarting the events that led to today.
What is the Big Bang theory?
The Big Bang theory represents cosmologists ' best attempts to reconstruct the 14 billion year story of the universe based on the sliver of existence visible today. Different people use the term "Big Bang" in different ways.
What did Hubble's observations show about the Milky Way?
Edwin Hubble dealt this story an experimental blow in the 1920s when his observations showed both that galaxies outside the Milky Way existed, and that their light appeared stretched — a sign that they were rushing away from Earth.
What does the mental image of an explosion mean?
It implies a central point, an expanding frontier, and a scene where light shrapnel flies faster than heavier chunks. But an expanding universe looks nothing like that, he said.
What is the strongest evidence for the Big Bang?
Known as the cosmic microwave background (CMB) radiation , many researchers consider it the strongest evidence for the Big Bang.
Is the Big Bang a bad term?
In later interviews, Hoyle denied intentionally inventing a slanderous name, but the moniker stuck, much to the frustration of some. "The Big Bang is a really bad term," said Paul Steinhardt, a cosmologist at Princeton. "The Big Stretch would capture the right idea.". The mental image of an explosion causes all kinds of confusion, ...
When did Alan Guth propose the first fraction of a second?
Alan Guth proposed a new picture of the first fraction of a second in the 1980s, suggesting that the universe spent its earliest moments growing exponentially faster than it does today. At some point this process stopped, and putting on the brakes produced a dense and hot (but not infinitely so) mess of particles that takes the place of the singularity. "In my own mind I think of that as the Big Bang, when the universe got hot," Farrar said.
Where did the evidence for the Big Bang come from?
Evidence for the Big Bang comes from detailed data from the Cosmic Background Explorer (COBE) and Wilkinson Microwave Anisotropy Probe (WMAP) satellites. In 1992, COBE produced the first good CMB map (top); nine years later, WMAP followed with a far-more detailed version. NASA/WMAP Science Tea.
What is the Big Bang?
Virtually all astronomers and cosmologists agree the universe began with a “big bang” — a tremendously powerful genesis of space-time that sent matter and energy reeling outward.
How long after the Big Bang did inflation occur?
NASA/WMAP Science Tea. The universe cooled rapidly as it blew outward, however, and by 10–35 second after the Big Bang, the epoch of inflation occurred, enlarging the universe by a factor of 1050 in only 10–34 second. During this wild period, cosmic strings, monopoles, and other exotic species likely came to be.
What happened before the Big Bang?
When the Big Bang occurred, matter, energy, space, and time were all formed, and the universe was infinitely dense and incredibly hot. The often-asked question “What came before the Big Bang?” is outside the realm of science because it can’t be answered by scientific means. In fact, science says little about the way the universe behaved until some 10–43 second after the Big Bang, when the Grand Unification Epoch began (and lasted only until about 10–35 second). Matter and energy were interchangeable and in equilibrium during this period, and the weak and strong nuclear forces and electromagnetism were all equivalent.
What happened to the universe after inflation?
After inflating, the universe slowed down its expansion rate but continued to grow, as it does still.
How long did the universe last after the Big Bang?
In fact, science says little about the way the universe behaved until some 10–43 second after the Big Bang, when the Grand Unification Epoch began (and lasted only until about 10–35 second). Matter and energy were interchangeable and in equilibrium during this period, and the weak and strong nuclear forces and electromagnetism were all equivalent.
How long after the Big Bang did dark matter start?
They are more interested in how the first astronomical objects, the large-scale inhabitants of the universe, came to be about 1 billion years after the Big Bang. But before these astronomers can gain a clear picture of that process, they need to consider the role of the wild card — dark matter. 0. JOIN THE DISCUSSION.
When did the Big Bang happen?
The Big Bang is thought to have occurred when something kicked off the expansion of a tiny singularity, some 13.8 billion years ago.
What is the Big Bang?
This process is now referred to as the Big Bang, a term first coined by Sir Fred Hoyle during a British Broadcasting Corporation (BBC) radio broadcast in 1950. Although the term implies some kind of explosion, there really wasn’t an outburst or a bang. It was really the rapid expansion of space and time.
What happened to the universe once the singularity was created?
However, once the singularity was created (however it happened), physicists have a good idea of what occurred next. The universe was in a hot, dense state and began to expand through a process called inflation. It went from very small and very dense, to a very hot state. Then, it cooled as it expanded.
What happened to the universe in the first few minutes?
As the universe began to cool during the first few minutes, protons and neutrons began to form. Slowly, protons, neutrons, and electrons came together to form hydrogen and small amounts of helium. During the billions of years that followed, stars, planets, and galaxies formed to create the current universe.
What did the two men discover about the universe?
The CMB had been predicted by a theory called the Big Bang, which suggested that the universe began as a densely hot point in space and suddenly expanded outward. The two men's discovery was the first evidence of that primordial event.
What is the origin of the universe?
What started the birth of the universe? According to physics, the universe sprang into existence from a singularity — a term physicists use to describe regions of space that defy the laws of physics. They know very little about singularities, but it's known that such regions exist in the cores of black holes. It's a region where all the mass gobbled up by a black hole gets squeezed into a tiny point, infinitely massive, but also very, very small. Imagine cramming Earth into something the size of a pinpoint. A singularity would be smaller.
Why did Einstein modify his theory?
Einstein’s theory was only later modified to accommodate the way the universe appears to be expanding. And, expansion is a big part of the story, particularly as it involves the existence of dark energy. Finally, a recalculation of the mass of the universe seems to support the Big Bang theory of events.
How old is the Big Bang?
And we don't see any objects obviously older than 13.7 billion years, suggesting that our universe came into being around that time.
What is the Big Bang theory?
Traditional Big Bang theory posits that our universe began with a singularity — a point of infinite density and temperature whose nature is difficult for our minds to grasp. However, this may not accurately reflect reality, researchers say, because the singularity idea is based on Einstein's theory of general relativity.
What is the timeline of the universe based on?
This graphic shows a timeline of the universe based on the Big Bang theory and inflation models. (Image credit: NASA/WMAP)
How fast did the universe expand?
At that point, they believe, the universe underwent an extremely brief and dramatic period of inflation, expanding faster than the speed of light. It doubled in size perhaps 100 times or more, all within the span of a few tiny fractions of a second. [ The Big Bang to Now in 10 Easy Steps]
How long ago was the universe born?
Our universe was born about 13.7 billion years ago in a massive expansion that blew space up like a gigantic balloon. That, in a nutshell, is the Big Bang theory, which virtually all cosmologists and theoretical physicists endorse. The evidence supporting the idea is extensive and convincing. We know, for example, that the universe is still ...
What is the oldest galaxy in the universe?
The galaxy is touted as the oldest, most distant one yet seen by Hubble. This field -- called HUDF09 – is the deepest infrared image ever taken of the universe. (Image credit: NASA, ESA, Garth Illingworth (University of California, Santa Cruz) and Rychard Bouwens (University of California, Santa Cruz and Leiden University) and the HUDF09 Team.)
What is the name of the four dimensional part of the universe?
Our four-dimensional part of the universe is called a brane (short for membrane). There could be other branes lurking out there in 11-dimensional space, the idea goes. A collision between two branes could have jolted the universe from contraction to expansion, spurring the Big Bang we see evidence of today.
Who predicted the Big Bang?
Undeterred by sceptics, scientists Ralph Alpher, George Gamow and Robert Herman predicted that if there had been a Big Bang, then a faint afterglow should linger somewhere in the Universe, and we should in theory be able to detect it. To do so would require one of the greatest pieces of fortune in science.
How was the universe created?
In 1927, he proposed that the Universe began as a large, pregnant and primeval atom, exploding and sending out the smaller atoms that we see today.
How long did it take for protons and neutrons to form?
Protons and neutrons started to form within the first second; within minutes these protons and neutrons could fuse and form hydrogen and helium nuclei. After 300,000 years, nuclei could finally capture electrons to form atoms, filling the Universe with clouds of hydrogen and helium gas.
What was the problem with the radio antenna in the 1960s?
The radio antenna they were using kept picking up a persistent weak hiss of radio noise. Rebuilding the antenna couldn’t get rid of the noise.
When did matter come into existence?
Around 13.8 billion years ago, all the matter in the Universe emerged from a single, minute point, or singularity, in a violent burst. This expanded at an astonishingly high rate and temperature, doubling in size every 10-34 seconds, creating space as it rapidly inflated.
When did Hubble discover the universe?
His idea went largely unnoticed. But in 1929 astronomer Edwin Hubble discovered that the Universe isn’t static but is in fact expanding.
How many stars are there in the Milky Way?
By our best estimates there are around 100 billion stars in the Milky Way and at least 140 billion galaxies across the Universe. If galaxies were frozen peas, there would be enough to fill an auditorium the size of the Royal Albert Hall.
How long ago was the Big Bang?
Image by ESA/Hubble/NASA. The Big Bang happened some 13 billion years ago. Before this time, as best we can tell, there was no time (or space, for that matter). If there was anything before the Big Bang, we can’t study it or say anything about it due to the constraints placed on us by the physics of our universe.
What happened to space during the Big Bang?
Rather, the Big Bang was space itself expanding. When the Big Bang happened, everything was in one location. Think of it as an infinitesimally small point. Then that point expanded until we get the universe we have today.
Was space growing everywhere?
To be absolutely clear, space was literally growing everywhere .
Can we go back to a time before the Big Bang?
In short, we can’t go back to a time before the Big Bang. So we can’t know what was there.
Can you find the center of the universe in the same place as the observer?
Therefore, if you use the light horizon to determine the center of the universe, you will always find it to be in roughly the same place as the observer. You can find a really cool example of this effect here.
What was the Big Bang theory?
The Big Bang marked the origin of the universe, the beginning of its expansion from a singularity (or something close to a singularity), a single point that was infinitely small, infinitely hot, and infinitely dense.
How long after the Big Bang did the universe expand?
From the moment of initial expansion to 10 -43 seconds afterwards, cosmologists suspect that the four fundamental forces at work in ...
What happened during the elementary particle era?
As the universe cooled, the temperature dipped too low to re-create pairs of particles from photons and the particles continued to annihilate without being replaced. A slight asymmetry between the amount (or possibly the behavior) of matter and antimatter enabled matter to dominate and become the universe’s primary ingredient. The cooler temperature also enabled the strong nuclear force to draw quarks together to form protons and neutrons.
How long did the era of atoms last?
The Era of Atoms (380,000 years – 1 billion years or so) began as the universe finally cooled and expanded enough for the nuclei to capture free electrons, forming fully-fledged, neutral atoms. Previously trapped photons were finally free to move through space, and the universe became transparent for the first time. These photons have been passing through space ever since, forming the cosmic microwave background. The expansion since the origin of the universe has redshifted the initially energetic photons to microwave wavelengths. The CMB also marks the furthest point back in time we can observe — the time before is sometimes referred to as the dark ages.
Why did the temperature of the universe drop?
As the universe cooled, the temperature dipped too low to re-create pairs of particles from photons and the particles continued to annihilate without being replaced. A slight asymmetry between the amount (or possibly the behavior) of matter and antimatter enabled matter to dominate and become the universe’s primary ingredient.
What happened at the beginning of the Electroweak Era?
At the beginning of the Electroweak Era (10 -35 to 10 -10 seconds), the strong force decoupled from the electroweak force, releasing a tremendous amount of energy and triggering a sudden rapid expansion known as inflation. As space expanded more rapidly than the speed of light, extremely energetic interactions created elementary particles such as ...
How old was the universe when the first galaxies formed?
The differences in density seen in the CMB provided the seeds for galaxy formation. The first galaxies formed when the universe was roughly 1 billion years old and heralded the current Era of Galaxies.
