Tonight's Nova (The universe is accelerating!)

[wviperw]

Well I knew the universe was expanding people! It was teh accelerating part I thought was interesting.

 

[Tom]

I love Nova. I knew about the acceleration but it was explained very well and it was interesting seeing how Supernova are found, classified, etc.

There may be a few people here on Anandtech that know everytihng there is to know, but I doubt it.
:moon:

 

[hdeck]

Originally posted by: wviperw
Oh cmon, you know chicks dig guys and their dark matter...

Anyway, one of the program's conclusions that they derived from the fact that the universe is accelerating is that, after the "big bang", the universe accelerated very quickly (explosion), slowed down, and is now accelerating again due to some unseen force. However, when I first heard them say it is accelerating, I figured it would mean that we are still IN the "big bang." Who is to say the explosion would not be long and drawn out? And in space, what is there to stop the debris from a constant acceleration? There is nothing to slow it down I don't think. Gravity wouldn't do it.

actually i've heard from physicists on tech tv (they interviewed some guy on the screen savers) that the universe has always been expanding.

 

[Arkitech]

Originally posted by: sandorski
Well, this will remain interesting until we find out that the acceleration is caused by a huge spherical wall that surrounds the universe. The gravitational force of the wall is drawing the universe to it, eventually we'll all die in a catastrophic SPLAT!

do you have any links to articles on that?

 

[RalphKramden]

No splatting for you. Your grandchildren to the 1,000,000 power won't see it.

 

[Arkitech]

Originally posted by: RalphKramden
No splatting for you. Your grandchildren to the 1,000,000 power won't see it.

darn

so that means I still have to go to work tommorow?

 

[silverpig]

Originally posted by: wviperw
Oh cmon, you know chicks dig guys and their dark matter...

Anyway, one of the program's conclusions that they derived from the fact that the universe is accelerating is that, after the "big bang", the universe accelerated very quickly (explosion), slowed down, and is now accelerating again due to some unseen force. However, when I first heard them say it is accelerating, I figured it would mean that we are still IN the "big bang." Who is to say the explosion would not be long and drawn out? And in space, what is there to stop the debris from a constant acceleration? There is nothing to slow it down I don't think. Gravity wouldn't do it.

A constant acceleration requires a constant force to be applied. If you are near a bomb in space and it goes off, you would accelerate very quickly and then just continue at your new speed. You wouldn't be accelerating anymore.

Gravity most certainly would slow stuff down. In fact, that is what was though was happening up until a few years ago. We assumed the universe was still expanding but that gravity was slowing it down. Whether is slowed it down enough to collapse into a crunch was something we didn't know.

 

[silverpig]

Originally posted by: hdeck

Originally posted by: wviperw
Oh cmon, you know chicks dig guys and their dark matter...

Anyway, one of the program's conclusions that they derived from the fact that the universe is accelerating is that, after the "big bang", the universe accelerated very quickly (explosion), slowed down, and is now accelerating again due to some unseen force. However, when I first heard them say it is accelerating, I figured it would mean that we are still IN the "big bang." Who is to say the explosion would not be long and drawn out? And in space, what is there to stop the debris from a constant acceleration? There is nothing to slow it down I don't think. Gravity wouldn't do it.

actually i've heard from physicists on tech tv (they interviewed some guy on the screen savers) that the universe has always been expanding.

Yeah, it has been, but expanding != accelerating.

 

[silverpig]

Originally posted by: sandorski
Well, this will remain interesting until we find out that the acceleration is caused by a huge spherical wall that surrounds the universe. The gravitational force of the wall is drawing the universe to it, eventually we'll all die in a catastrophic SPLAT!

Actually, if there was a huge spherical wall, we wouldn't be pulled outwards at all. The part of the sphere we are closest to has little mass compared to the part of the sphere farther away from us. If you do the integrals up all correcty, I believe you get a net cancellation of forces. So no splat for us

 

[Arkitech]

Originally posted by: silverpig

Originally posted by: sandorski
Well, this will remain interesting until we find out that the acceleration is caused by a huge spherical wall that surrounds the universe. The gravitational force of the wall is drawing the universe to it, eventually we'll all die in a catastrophic SPLAT!

Actually, if there was a huge spherical wall, we wouldn't be pulled outwards at all. The part of the sphere we are closest to has little mass compared to the part of the sphere farther away from us. If you do the integrals up all correcty, I believe you get a net cancellation of forces. So no splat for us

damn so this really means I have to go to work tommorow

 

[bleeb]

This makes me think about the area that the universe is expanding to, what is there?

 

[Arkitech]

this is kind of off topic but does anyone remember an episode of where they were trying to get a glimpse of some of the sea creatures that lived almost on the very bottom of the ocean floor. I guess because the pressure of the water is so great its impossible for a human to dive to those depths and its even difficult to get equipment down that deep. Anyway the show was talking about a infrared photograph of some kind of creature that 2-3x the size of the largest whale. I did'nt get a chance to finish watching the entire show but it was really interesting.

 

[oLLie]

Originally posted by: bleeb
This makes me think about the area that the universe is expanding to, what is there?

Moebius strip universe. BAM! Next.

 

[oLLie]

Originally posted by: Arkitech
this is kind of off topic but does anyone remember an episode of where they were trying to get a glimpse of some of the sea creatures that lived almost on the very bottom of the ocean floor. I guess because the pressure of the water is so great its impossible for a human to dive to those depths and its even difficult to get equipment down that deep. Anyway the show was talking about a infrared photograph of some kind of creature that 2-3x the size of the largest whale. I did'nt get a chance to finish watching the entire show but it was really interesting.

Yeah man. Nova (and to a greater extent public broadcasting) is great. I find it interesting that it usually has less commercials (interrupting the program) than cable TV.

 

[TheShiz]

Originally posted by: oLLie

Originally posted by: Arkitech
this is kind of off topic but does anyone remember an episode of where they were trying to get a glimpse of some of the sea creatures that lived almost on the very bottom of the ocean floor. I guess because the pressure of the water is so great its impossible for a human to dive to those depths and its even difficult to get equipment down that deep. Anyway the show was talking about a infrared photograph of some kind of creature that 2-3x the size of the largest whale. I did'nt get a chance to finish watching the entire show but it was really interesting.

Yeah man. Nova (and to a greater extent public broadcasting) is great. I find it interesting that it usually has less commercials (interrupting the program) than cable TV.

um, pbs here has no commercials in the shows, there is a little break between programs, but when shows come on it runs through, which is great. Pretty much all I watch is PBS and c-span so I don't see a lot of ads.

 

[Byte]

This is pretty old news, it was the discovery of the year in 98. Two teams (one from Australia and on from Berkley) worked on this seperatly and found that the redshifts for the supernova were showing the universe accelerating at probably faster than exponential rates, meaning Hubbles law needs revision. Both teams did this seperatly and when they compared their findings (which they thought were wrong) they were amazed how similar they were. This can only be explained by "Dark Energy." Einstein had once came up with a cosmological constant in which the universe would be balanced. No one accepted this idea and this was thought to be his huge blunder. But it may be other force causing the universe to expand. A very good theory would be "quintessence" or a force opposite of gravity. If you thinkg about it, all our forces have oppsites....Why not gravity? I can't believe something so simple is so easily overlooked.

Dark matter has been in debate for some time. The way we detect it is by the rotation velocity of galaxies. As you probably all know, when something spins, the outside spins slower than the inside in angular velocity. But they found that galaxies spin at the same rate from inner to outer edges. This is crazy, and defies all current common sense and also newtons laws. So there must be either more mass (dark matter...) or something we don't know about in galactic differences. I think that newtons laws break down at such large distances similar to how it breaks down in high velocities. So dark matter may one day be an invention to these guys who can't get the math right (imagine taking an exam, you don't know whats going on, then just make something up, thats what they basically did!). They pretty much ruled out most of known matter such as neutrinos (a couple months ago in fact they sucessfully finished experiments that proved this). But a few other phenomenon do not totally do away with dark matter such as extreme gravitational lensing and collision of visible and invisible galaxies. This will be a neverending issue, we'll probably never solve these until we create warp drives... (go star trec freaks!)

 

[PCMarine]

PBS has some damn good specials.