Register | Sign In


Understanding through Discussion


EvC Forum active members: 65 (9162 total)
2 online now:
Newest Member: popoi
Post Volume: Total: 915,817 Year: 3,074/9,624 Month: 919/1,588 Week: 102/223 Day: 13/17 Hour: 0/0


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   An observation of big bang by a layman
2ice_baked_taters
Member (Idle past 5851 days)
Posts: 566
From: Boulder Junction WI.
Joined: 02-16-2006


Message 1 of 12 (289675)
02-23-2006 1:03 AM


I have a thought and someone please set me on the right path if I am lost.
Under the pretext of big bang:
As I comprehend concerning the detectable universe...we are seeing a thin slice of a cone shaped wedge with respect to the point source.
I am not aware of the rate of expansion but I am guessing it must be at or near the speed of light.
The matter on the opposing side of the point source from our location should be traveling at or near twice the speed of light with respect to us. We will never detect it.
If this is true: There must be a degree of vector, {with respect to the point source} away from our own where we are incapable of detection because the objects will be moving away faster than the speed of light and evidence of them we will never see? If this is true there is a substantial portion of the universe we will be forever blind to?
This message has been edited by 2ice_baked_taters, 02-23-2006 10:21 AM
This message has been edited by 2ice_baked_taters, 02-23-2006 10:21 AM
This message has been edited by 2ice_baked_taters, 02-23-2006 12:21 PM

Replies to this message:
 Message 2 by AdminNWR, posted 02-23-2006 1:23 AM 2ice_baked_taters has replied
 Message 5 by Modulous, posted 02-23-2006 6:59 PM 2ice_baked_taters has replied
 Message 6 by nwr, posted 02-23-2006 7:29 PM 2ice_baked_taters has not replied
 Message 7 by cavediver, posted 02-23-2006 9:17 PM 2ice_baked_taters has replied

  
AdminNWR
Inactive Member


Message 2 of 12 (289679)
02-23-2006 1:23 AM
Reply to: Message 1 by 2ice_baked_taters
02-23-2006 1:03 AM


Needs a more descriptive title
Your title does not even hint at a question on cosmology.
Edit your message, to change the title to something more descriptive. Then reply to this message, so we will know that you want us to take a new look at your topic.

This message is a reply to:
 Message 1 by 2ice_baked_taters, posted 02-23-2006 1:03 AM 2ice_baked_taters has replied

Replies to this message:
 Message 3 by 2ice_baked_taters, posted 02-23-2006 5:41 PM AdminNWR has not replied

  
2ice_baked_taters
Member (Idle past 5851 days)
Posts: 566
From: Boulder Junction WI.
Joined: 02-16-2006


Message 3 of 12 (289867)
02-23-2006 5:41 PM
Reply to: Message 2 by AdminNWR
02-23-2006 1:23 AM


Re: Needs a more descriptive title
Diss b better?

This message is a reply to:
 Message 2 by AdminNWR, posted 02-23-2006 1:23 AM AdminNWR has not replied

  
AdminNWR
Inactive Member


Message 4 of 12 (289870)
02-23-2006 6:41 PM


Thread moved here from the Proposed New Topics forum.

  
Modulous
Member
Posts: 7801
From: Manchester, UK
Joined: 05-01-2005


Message 5 of 12 (289876)
02-23-2006 6:59 PM
Reply to: Message 1 by 2ice_baked_taters
02-23-2006 1:03 AM


This is an interesting start to answering your question.
However, for the simplest interpretation of your question, the answer is that the universe does expand faster than the speed of light, and, perhaps more surprisingly, some of the galaxies we can see right now are currently moving away from us faster than the speed of light! As a consequence of their great speeds, these galaxies will likely not be visible to us forever; some of them are right now emitting their last bit of light that will ever be able to make it all the way across space and reach us (billions of years from now). After that, we will observe them to freeze and fade, never to be heard from again.
I'm unsure if there are any galaxies are beyond us yet, I think the answer is no, but I could be wrong. After all, cosmologists do discuss The Visible Universe, so I suppose that implies there is a non-visible part of it.

This message is a reply to:
 Message 1 by 2ice_baked_taters, posted 02-23-2006 1:03 AM 2ice_baked_taters has replied

Replies to this message:
 Message 9 by cavediver, posted 02-23-2006 9:29 PM Modulous has not replied
 Message 11 by 2ice_baked_taters, posted 02-23-2006 11:01 PM Modulous has not replied

  
nwr
Member
Posts: 6408
From: Geneva, Illinois
Joined: 08-08-2005
Member Rating: 5.1


Message 6 of 12 (289884)
02-23-2006 7:29 PM
Reply to: Message 1 by 2ice_baked_taters
02-23-2006 1:03 AM


I am not aware of the rate of expansion but I am guessing it must be at or near the speed of light.
The matter on the opposing side of the point source from our location should be traveling at or near twice the speed of light with respect to us. We will never detect it.
As pointed out in Expanding universe., it is space itself that is expanding. Your description doesn't quite work.
But let's pretend that it does work. Let's suppose that there is a point P in space, so that some galaxy G is moving in one direction away from P at almost the speed of light. And our galaxy is moving away in the opposite direction. That seems almost as if, relative to use, galaxy G should be moving away from us at almost twice the speed of light.
It doesn't work that way. Because we are moving at a different velocity from the observer at P, we are in a different inertial frame. We must transform the observations at P into the coordinates we use in our inertial frame. When we have done the transformation, P seems to me moving away from us at close to the velocity of light. Galaxy G appears to be moving away from us at a speed even closer to the velocity of light. The transformed velocity - what we observe in our inertial frame - is not greater than the velocity of light.
The light from P will be red-shifted. The we receive from G will be even more red-shifted. But the photons will reach us (unless blocked).
At least that is how I understand it.

This message is a reply to:
 Message 1 by 2ice_baked_taters, posted 02-23-2006 1:03 AM 2ice_baked_taters has not replied

Replies to this message:
 Message 8 by cavediver, posted 02-23-2006 9:22 PM nwr has not replied

  
cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 7 of 12 (289908)
02-23-2006 9:17 PM
Reply to: Message 1 by 2ice_baked_taters
02-23-2006 1:03 AM


Yes, you are correct. Though it is not correct to say that the expansion has a velocity as such: it has a velocity per distance scale... which we call the Hubble Constant - roughly 70km/s per Mega Parsec (~3 million light years). So there comes a distance at which it appears that galaxies are receding at the speed of light. And beyond those galaxies are galaxies that are forever out of causal contact with us, as you suggest.
There is a good chance the universe is infinite... in which case there is quite a bit more beyond the observable universe than actually in it!

This message is a reply to:
 Message 1 by 2ice_baked_taters, posted 02-23-2006 1:03 AM 2ice_baked_taters has replied

Replies to this message:
 Message 10 by 2ice_baked_taters, posted 02-23-2006 10:28 PM cavediver has not replied

  
cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 8 of 12 (289909)
02-23-2006 9:22 PM
Reply to: Message 6 by nwr
02-23-2006 7:29 PM


You had it right at the beginning of your post... you are not dealing with velocities, but expansions of space. So you can't use the velocity addition law from SR. There is an awful lot of curvature between the two galaxies receding from us at c on diametrically opposite sides of the sky...

This message is a reply to:
 Message 6 by nwr, posted 02-23-2006 7:29 PM nwr has not replied

  
cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 9 of 12 (289910)
02-23-2006 9:29 PM
Reply to: Message 5 by Modulous
02-23-2006 6:59 PM


I'm unsure if there are any galaxies are beyond us yet
From the moment of the BB there were areas of space out of causal contact with us. This very fact leads to the horizon problem or paradox (thermal equilibrium of the CMBR) that is resolved by inflation. Inflation would suggest that the observable universe is an infinitesimal fraction of the total (finite or infinite) universe.

This message is a reply to:
 Message 5 by Modulous, posted 02-23-2006 6:59 PM Modulous has not replied

  
2ice_baked_taters
Member (Idle past 5851 days)
Posts: 566
From: Boulder Junction WI.
Joined: 02-16-2006


Message 10 of 12 (289912)
02-23-2006 10:28 PM
Reply to: Message 7 by cavediver
02-23-2006 9:17 PM


Yes, you are correct. Though it is not correct to say that the expansion has a velocity as such: it has a velocity per distance scale... which we call the Hubble Constant - roughly 70km/s per Mega Parsec (~3 million light years). So there comes a distance at which it appears that galaxies are receding at the speed of light. And beyond those galaxies are galaxies that are forever out of causal contact with us, as you suggest.
There is a good chance the universe is infinite... in which case there is quite a bit more beyond the observable universe than actually in it!
I had never heard my point addressed before.
It brings a new perspective to what is beyond the pond.
From a person like me who has interests in such things I greatly apreciate those like you. In my life I do not have the time to devote to inhaling all the info it might take to run across the answer to this question. Likely, in places on the web that might actually discuss the idea I would be clueless to the math involved. I would also be ignorant of many of the terms used so even if I did come across it I would not likely have a clue what I was looking at. Those involved assume you have 6-8 years of math and physics under your belt. I happened to have never graduated high school. Thank you
This message has been edited by 2ice_baked_taters, 02-23-2006 10:30 PM

This message is a reply to:
 Message 7 by cavediver, posted 02-23-2006 9:17 PM cavediver has not replied

  
2ice_baked_taters
Member (Idle past 5851 days)
Posts: 566
From: Boulder Junction WI.
Joined: 02-16-2006


Message 11 of 12 (289913)
02-23-2006 11:01 PM
Reply to: Message 5 by Modulous
02-23-2006 6:59 PM


This is an interesting start to answering your question.
Thank you for the link.
By this I am understanding that what we see in space is a record of history played out before us in light or various portions of the electomagnetic spectum depending upon what medium you use for detection. Much of what we see with real time respect to us is in fact now beyond our ability to detect.
Wow.....We could have come along at a time when the night sky was truly black.

This message is a reply to:
 Message 5 by Modulous, posted 02-23-2006 6:59 PM Modulous has not replied

  
2ice_baked_taters
Member (Idle past 5851 days)
Posts: 566
From: Boulder Junction WI.
Joined: 02-16-2006


Message 12 of 12 (289915)
02-23-2006 11:03 PM


Were my life different I would likely be doing research right now.

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2023 by EvC Forum, All Rights Reserved

™ Version 4.2
Innovative software from Qwixotic © 2024