Question

how old does the big bang theory say the universe is

Answer 1

13.77 billion years

Answer 2

What he said ^^ xD

Answer 3

They say the earth can't be older than 13 billion years old. I don't believe the Big Bang Theory myself but, I read this in my school.

Answer 4

Big bang theory is all about considerations and imaginations. There is no experimental proof present for it. Big minds thought that it might happened.

Answer 5

Exactly. It's not science it's practically a religion.

Answer 6

It is all about science fiction.

Answer 7

We can come up with the idea that If we assume that the velocity of galaxies are the same (no acceleration), then the velocity of a galaxy, v, and the distance travelled, d and the time is the age of the universe,
d=vt, but using hubble's law, v=Hd, \(H= 70 km s^{-1}Mpc^{-1}\)
d=Hdt
So the time is
\[t=\frac{1}{H} \\ \\ t \approx 4.3 \times 10^{17}s\]
Which is about 14 billion years

Answer 8

Why big bang theory you guys ask?!?

well initially people thought that the universe was static.. but later they realized that the universe is not really static.. but its actually expanding!!
there is EXPERIMENTAL evidence for that.. the hubble space telescope images :P
so now tell me.. if you see that something is expanding in all directions all the time.. if someone asked you.. "hey what do you think was the beginning of that thing??" whats your answer??

you would say.. well since it keeps on expanding that means when it started out.. it must have been TINNIE TINY.. cause thats LOGICAL!!.. get it guys? :p

P.S. "Exactly. It's not science it's practically a religion." lol that was hilarious :D

Answer 9

@mashy do we consider space as Energy or matter?

Answer 10

well.. i dunno.. i think the jury is still out on that one.. :P .. when we have dark energy and dark matter.. and the cosmological constant!..

Answer 11

if the universe started with explosion which we generally call Big bang,
energy is and matter are constant but converting from one form to other. then why space in growing bigger and bigger. do you mean space has also took birth from the explosion.
Im very sorry to trouble you with my mad questions.

Answer 12

I didn't quite get your question.. but are you asking me that energy should be conserved ?! :P..and yes.. thats a nice thought.. you may say if it started from nothing.. then initially there was no energy.. and now there is .. how come?

well the answer is.. *Drum roll*.. the total energy of the universe IS ZERO.. yup :D.. because all the matter and everything else has positive energy (including you and me.. and the energy m using to TYPE this :D).. however gravity my friend gives NEGATIVE energy.. so if i sum them up at the entire universal scale then the total energy is found to be zero.. provided we accept the fact that the universe is FLAT (like a paper)..so that solves the energy problem

Answer 13

is the universe expanding or distance between galaxies increasing?

Answer 14

the space itself is expanding.. so yes the universe is expanding!

Answer 15

if I consider space as expanding balloon, to expand balloon continuously I should continuously supply air to it Let me consider this as energy supplied by me to expand balloon. My question is, what is that secret energy, which is continuously expanding this universe.

Answer 16

im sorry if I trouble you @Mashy .

Answer 17

well i could just tell you imagine this A FANTASTIC explosion took place.. and this is just the aftermath of the explosion.. so your question what is making the universe expand is just like when you pump in air the balloon expands.. all the air that was needed was pumped in at the time of the big bang .. and thus the balloon (our universe is expanding till date).. this makes sense.. so the universe would be slowing down.. and this was the accepted theory.. but around 1999 they found that the universe was not slowing down rather it was speeding up the expansion i mean.. so

yes you are correct now in asking where is this energy coming from. and that energy is called as dark energy comes from the concept of COSMOLOGICAL constant.. it was actually given by Einstien.. now i m gonna be honest i dnnno much about that stuff.. but i think what that says is that even empty space produces repelling force.. that is the force thats making our universe expand at an accelerating rate!

Answer 18

I have a problem with a lot of things that have been said in this thread.... Space is neither matter nor energy, and yes, the Big Bang theory says that space was born at the moment of that colossal explosion.

Saying that the Big Bang theory is like a religion is complete nonsense. Scientific thought is the complete opposite of religious dogma -- if it were a religion, we would not be constantly seeking more experimental evidence to verify and possibly augment the theory. We would simply be taking it as fact and moving on. This is not true -- it is our best model of the early universe, and as our experiments and theory progress, so will our understanding of it.

Answer 19

Empty space has energy ..called vacuum energy!

Answer 20

I didn't say it doesn't have energy, I said it is not energy itself. If you want to be poetic, energy and matter are the players and spacetime is the stage.

Answer 21

oh yea ofcourse.. its not energy ITSELF or matter ITSELF true :D.. according to our current understanding that is :P