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Astrophysicists propose new twist on Big Bang

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Re: Astrophysicists propose new twist on Big Bang

#31

Post by dhimes »

fragmede wrote: post #25
Zarathust wrote: post #18

Earlier quoted context omitted.

I'm not sure of what a graviton is, but wikipedia tells me that it is not detectable by any current mean. I'd be tempted to say in light of this that their theory is not testable either. http://en.wikipedia.org/wiki/Graviton

> any current mean[s] But that's the point, innit. Who's to say we don't discover magic quantum carbon nanotubes or something thing that makes it feasible to setup a graviton detector at some point in the future. And who's to say it won't be useful, either. I'm serious; the Higgs-Boson was theorized to exist in 1964 , and was proven to exist only after great expense in 2012, utilizing many cutting edge technologies.…

At the point it we can test it, it becomes testable. The authors, note, did not claim it was testable. They simply indicated the direction research should go in order to test it.

As per Einstein, it's true that accurate measurements of his GR effects didn't come along for decades, but he was answering known physical problems. And the crude measurements of his day aligned with his predictions, they just weren't accurate yet.

Re: Astrophysicists propose new twist on Big Bang

#32

Post by jeangenie »

lutusp wrote: post #22
pawn wrote: post #7

Earlier quoted context omitted.

It's always been my understanding that the normal laws of physics don't work at big bang time as well. One thing I've wondered about is how people are so adamantly confident in the theory of the Big Bang in light of this. Is it simply because they don't like the alternatives, because they've never been heard an alternative, or is there a better reason?

> It's always been my understanding that the normal laws of physics don't work at big bang time as well. That's wrong. As soon as the universe's mass/energy expanded sufficiently for there to be a time dimension (IOW as soon as the universe was something other than a singularity), the present physical laws applied. Some of the physical constants with which we are familiar may have had different values, but the same s…

It's amusing how confidently you state "wrong" and then make the same logical error in using a time-dependent conjunction ("As soon as...") in your own description.

Re: Astrophysicists propose new twist on Big Bang

#33

Post by lutusp »

jeangenie wrote: post #32
lutusp wrote: post #22

Earlier quoted context omitted.

> It's always been my understanding that the normal laws of physics don't work at big bang time as well. That's wrong. As soon as the universe's mass/energy expanded sufficiently for there to be a time dimension (IOW as soon as the universe was something other than a singularity), the present physical laws applied. Some of the physical constants with which we are familiar may have had different values, but the same s…

It's amusing how confidently you state "wrong" and then make the same logical error in using a time-dependent conjunction ("As soon as...") in your own description.

The OP specified a time other than zero, so there are four dimensions. This means the usual physical rules apply. My use of "as soon as" is completely consistent with the era specified by the OP, i.e. when four dimensions are available and physics is "normal". And I made this perfectly clear in my reply.

Re: Astrophysicists propose new twist on Big Bang

#34

Post by noobermin »

jafaku wrote: post #24
noobermin wrote: post #13

Earlier quoted context omitted.

You apparently were flagged by a theoretical physicist. A lot of "physicists" nowadays forget that we're supposed to be scientists, not dreamers. Dreams are nice, but experiment and observations valid theory. I agree. Unless this has some modifications to the current model of the big bang which leads to _observable_effects_ , I don't know if this theory could even be validated as...well theory.

You know theory means explanation, not imagination, right?

I use the definition for theory as a hypothesis that has received sufficient experimental validation. So, by definition, many of the frontier quantum-gravity stuff doesn't fit this, unfortunately as compelling and fascinating as they are.

Again, I'm just agreeing with what s/he said, that unless we have experiment/observation, we don't know whether this really describes our universe's origins and/or evolution.

Re: Astrophysicists propose new twist on Big Bang

#35

Post by coldtea »

trhway wrote: post #2

>The researchers emphasize that this idea, though it may sound absurd, is grounded firmly in the mathematics describing space and time. Specifically they’ve used the tools of holography to “turn the big bang into a cosmic mirage.” embedding into higher dimension spaces (or in general - into more "richer" structures) is a convenient mathematical tool and it works nice ... in mathematics. To work in physics that higher…

>embedding into higher dimension spaces (or in general - into more "richer" structures) is a convenient mathematical tool and it works nice ... in mathematics. To work in physics that higher dimension space must really exist.

I'd put my money on those Phds in physics knowing that already.

They probably heard about Occam too.

Building a model based on specific reading on the current knowledge of physics, intuitions that hold true in light of this knowledge, and some mathematical tools, is a valid process, despite not being immediately empirically checkable. The "exists" part can be tested later.

That doesn't make their work equal to abitrary BS like "a 4d nut that a small 4d squirrel puppy is about to bite into".

Re: Astrophysicists propose new twist on Big Bang

#36

Post by jeangenie »

lutusp wrote: post #33
jeangenie wrote: post #32

Earlier quoted context omitted.

It's amusing how confidently you state "wrong" and then make the same logical error in using a time-dependent conjunction ("As soon as...") in your own description.

The OP specified a time other than zero, so there are four dimensions. This means the usual physical rules apply. My use of "as soon as" is completely consistent with the era specified by the OP, i.e. when four dimensions are available and physics is "normal". And I made this perfectly clear in my reply.

So you're saying there was a time when time was zero? You might keep me up all night chuckling.

Re: Astrophysicists propose new twist on Big Bang

#37

Post by collyw »

Sharlin wrote: post #20
pawn wrote: post #7

Earlier quoted context omitted.

It's always been my understanding that the normal laws of physics don't work at big bang time as well. One thing I've wondered about is how people are so adamantly confident in the theory of the Big Bang in light of this. Is it simply because they don't like the alternatives, because they've never been heard an alternative, or is there a better reason?

NASA uses Newtonian mechanics to send spacecraft to the outer planets and beyond. Everybody knows that Newtonian mechanics stop being accurate in certain conditions, but that does not prevent it being an incredibly useful model outside those conditions. The best experimentally-verified cosmological models we have point to the fact that the Universe was in a hot and dense state a few microseconds after a specific poin…

>Contrary to the popular belief, The Big Bang model simply does not concern itself with what happened at the exact moment of Big Bang; what it does is describe the evolution of the Universe after that, and does it well.

That sounds as much of a cop out as the answers religious people give.

Re: Astrophysicists propose new twist on Big Bang

#39

Post by collyw »

nitrogen wrote: post #21
collyw wrote: post #8

Earlier quoted context omitted.

It's basically a belief system at that stage. It doesn't provide any more believable answers than religion for me.

The big bang, unlike theology, tells us why distant objects are more red than close objects, why we can't see anything further than ~13bil light years away, why there is microwave noise everywhere, etc. The mathematics that describe all those things imply certain things about earlier cosmological history.

But still doesn't prove anything about where the universe "came from".

Re: Astrophysicists propose new twist on Big Bang

#40

Post by BgSpnnrs »

trhway wrote: post #2

>The researchers emphasize that this idea, though it may sound absurd, is grounded firmly in the mathematics describing space and time. Specifically they’ve used the tools of holography to “turn the big bang into a cosmic mirage.” embedding into higher dimension spaces (or in general - into more "richer" structures) is a convenient mathematical tool and it works nice ... in mathematics. To work in physics that higher…

>Otherwsie, for all we know, out Universe can be just a 3d surface of a 4d nut that a small 4d squirrel puppy is about to bite into.

absolutely. I know you are trying to portray such a scenario as incredulous, but it's entirely feasible.

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