How can you prove the big bang theory?

Answer 1

No theory can be proven beyond all doubt. But the big bang explains many phenomena which are not explained by any other theory of cosmology.

• The expanding universe: The universe is expanding. Not only is it expanding, but it is expanding at different rates. Galaxies relatively close to the Milky Way are moving away rather slowly while galaxies so far away they can barely be detected are moving away at incredible speeds. How can this be? Think of an elastic strip with three dots drawn in a row, one centimeter apart. Now stretch such that the distance between the dots is 2 centimeters. In the same time it took the second dot to move from 1 cm to 2 cm away from the first, the second dot moved from 2cm to 4 cm, i.e., the second dot moved twice as fast. So the universe is not a fixed space with galaxies moving through it, but a free but expanding space with objects more or less fixed inside it. The big bang theory explains this by postulating that 13.7 billion years ago, space existed as a singularity, but in an instant began to expand rapidly, taking matter with it.

• Olbers' Paradox: Hienrich Olbers was a European astronomer who noted that the universe could not be both infinitely large and infinitely old. If it were, then every line of sight would end in a star because there would be an infinite number of stars, and an infinite amount of time for their light to reach earth, so the entire night sky would be lit up with stars, one in every possible direction. The big bang theory gives a time for the birth of the universe, So the universe cannot be infinitely old, so even if it is infinitely large, stars which are more than 13.7 billion light years from earth would not be visible from earth.

• Cosmic Microwave Background Radiation: In the 1960's, researchers for a television network discovered a constant interference with their instruments. It was later that this background noise, or background radiation, was present everywhere, even in space. This background radiation is in the microwave range, and its presence gives the universe a constant temperature of 2.7 Kelvins (unless there's a sun or something to add more heat). The big bang theory explains this phenomena. Assuming the theory to be true, for the first several hindered thousand years of the universe, all that existed in space were electrons, quarks, leptons, and maybe a baryon here and there. A photon, a "packet" of energy, could not travel very far without hitting on of these things and scattering, so even if you could survive such conditions, you wouldn't be able to see anything except for maybe a blinding blur of light. At the time the photons had a large energy because of their high frequency. Eventually though, matter condensed into protons, neutrons, and such, leaving more and more space for the photons to travel. As space expanded, so did the wavelength of the photons, lowering the frequency, and subsequently their energy. Now, 13.7 billion years later, the wavelengths have dropped into the microwave range, and manifest themselves in the constant 2.7 Kelvins of microwave background radiation.

Answer 2

Some proof about the big bang is that scientists can use technology to pick up radiation from the earliest moments in the universe's evolution. Try switching on a channel on your TV you don't receive. 1% of that static is radiation from the first 5 seconds or so of the big bang. So if there's nothing on TV you can watch the birth of the universe.

But apart from that, there is no proof. Keep in mind that the Big bang theory is just a theory.

Answer 3

That our Universe has been expanding (NOT exploding) since about 13.7 billion years ago is supported by the following irrefutable facts:

1) The distance between our world and all galaxies outside our Local Group is expanding, and the rate of expansion away from us is proportional to the distance away from us. Since what we see of distant galaxies is what they were doing billions of years ago, it MUST be that this movement has been fairly constant over the last ten billion years or so. The rate of expansion is consistent with all matter being clumped together about 13 billion years ago.

2) If the BB is true, then, about 377,000 thousand years after the end of Inflation, photons were finally de-coupled from atoms, and have been moving in all directions ever since. If this is true, then there would be microwave radiation with a black-body spectrum, with temperature about 3.8 K, coming to us with almost isotropy. Eighteen years after this radiation was predicted, the mircrowaves found and was EXACTLY as predicted. All other hypotheses about the nature of our Universe can only say, "We only know that this microwave radiation exists, we have absolutely no explanation whatsoever for WHY it is there."

3) If the BB is true, our Universe should be about 90% hydrogen and about 10% helium. This is exactly what we see in all parts of our Universe. Again, no other hypothesis can explain why our Universe has this ratio of basic elements.

4) The ratio of long-lived (ie, half lives in giga-years) radioactive isotopes in our Universe to their decay products show a Universe of age 14+_ 2 billion years. This measurement is completely independent of the above derived ages.

The evidence for the Big Bang is as strong as the evidence for gravity outside our Earth.

Answer 4

The same way they know that gravity exists outside our Earth.

Both ideas make certain predictions about what we would see IF the ideas were true. If the idea is false, then we would fail to see what is predicted by that idea. This is a concept called "falsifiability" -- meaning we can show that an idea is false simply by testing whether we observe what the idea predicts we will observe.

1) *IF* gravitiy exists outside our Earth, then planetary orbits would be altered by an amount equal to the gravity from other planets. It was through this prediction that Neptune was firmly discovered.

2) *IF* Big Bang Cosmology is true, then we would see

a) an increasing distance between us and all distant galaxies, with the rate of increase in the distance being proportional to the distance.

b) a rate of increase in distance showing that, at about 13 billion years ago, all matter was almost infinitely more dense than it is today.

c) isotropic, microwave radiation coming from outside our Earth, with a spectrum equal to that of black-body radiation of temperature 2.7 K

d) hydrogen comprising about 90% of our Universe and helium about 10%.

e) quasars seen only far from our Earth.

f) no white dwarfs older than about 13 billion years.

g) long-lived radioactive isotopes in ratio to their decay products showing an age of the former to be no more than 13 billion years old.

If we fail to observe ANY of the above predictions, then intelligent people would have a reason to question Big Bang Cosmology. But we observe all of them. BBC is as firmly true as gravity.

This is all highly acceptable. The worrying thing is that long ago people thought for very obvious and demonstrably reasonable reasons, that the earth was flat. Also before a child is taught otherwise it is obvious that life/theworld is restricted to what people call the horizon. Wavelets on the sea get progressively crammed together as you peer closer to the horizon. The description has uncomfortable parallels with the big-bang theory. Who says time proceeds at a constant rate? Or that the universe hasn't always seemed to be 13 billion years old, even picoseconds (at our present clock rate) after what we like to call the big-bang.

Answer 5

Depends what you mean by "prove." If you mean, "Will convince someone who will not be convinced no matter how much evidence is presented," then (obviously) Big Bang Cosmology can never be "proven."

However, it is undeniable that the evidence in favor of Big Bang Cosmology (BBC) is as strong as the evidence for our Sun being in the center of our solar system. In both cases, all observational evidence favors it, and none argues against it.

Amongst the evidence in favor:

1) The distance between us and all distant galaxies is increasing, and the rate at which the distance is increasing is directly proportional to the distance between us and these galaxies.

2) There exists an isotropic (to one part in 10,000) and continuous radiation, with a spectrum of a blackbody at 2.7K. This is exactly as predicted by BBC, and allows to see light from our early Universe -- less than 400,000 years after the Big Bang.

3) The ratio of hydrogen to helium in all parts of our Universe are exactly as predicted by BBC.

4) The ratio of long-lived isotopes to their decay products shows decays began about 10 billion years ago.

All of the above are easy to explain with BBC. Proponents of all other hypotheses are reduced to saying, "I admit that's the truth, but I have no explanation for it."

Answer 6

If by "prove," you mean, "convince more than 75% of US citizens that it's true," then I suppose scientists can't even prove that the Earth goes around the Sun. In that sense, "proving" Big Bang Cosmology (BBC) may be as difficult as proving a heliocentric solar system.

HOWEVER, intelligent people can approach BBC and heliocentrism in the same scientific manner: ask the simple question, "What would we observe if BBC were true, that we would NOT see if BBC were false?" (or "if the Earth goes around the Sun?"), and then make the observation. If, on a repeated basis, we DO see what BBC predicts, when no other hypothesis makes that prediction, then it is safe to say that BBC has been "proven."

Amongst the things that BBC predicts that we will observe:

1) The distance between us and all distant galaxies is increasing, and the rate at which the distance is increasing is directly proportional to the distance between us and these galaxies.

2) There exists an isotropic (to one part in 10,000) and continuous radiation, with a spectrum of a blackbody at 2.7K. This is exactly as predicted by BBC, and allows to see light from our early Universe -- less than 400,000 years after the Big Bang.

3) The ratio of hydrogen to helium in all parts of our Universe are exactly as predicted by BBC.

4) The ratio of long-lived isotopes to their decay products show that some decays began about 10 billion years ago -- but none have been found older than that.

5) Quasars are seen far from us, but not close to us.

6) The absence of white dwarf stars older than about ten billion years.

All observational tests show that the space in our Universe has been expanding at a (more or less) constant rate for the last 13.7 billion years or so -- none contradict this. BBC is as proven as a heliocentric solar system.

Which doesn't mean that about 25% of people won't accept the idea that our Earth goes around our Sun.

Answer 7

It's quite obvious that the theory took place. You can read about the theory in scientific journals, Wikipedia, etc., so you can't really deny that such a theory exists.Note: If you want evidence that the "Big Bang" took place, as opposed to the "Big Bang theory", please ask a separate question.

Answer 8

The Big Bang Never happend God created all of everything that we have even us.

Answer 9

we can prove big bang theory through the expansion of universe ,through red shifts of galaxies and cosmic back ground radiation

Answer 10

Measurements of the distances between celestial bodies suggest that everything started from a single point in space.