What are the ideas behind galaxies moving apart, red shift and the age of the universe?

[5attab]

<p><font size="4">Im going to study about galaxies next year, and I want to have some knowledge about it and about what is going on, before my lessons so i dont go there with no idea.<br /></font></p><p><font size="4"><br />A good explanation would be greatly appreciated!</font></p><p><font size="4">So please help if u can!<br /> Thanx alot in advance!! </font></p>

 

[derekmcd]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Im going to study about galaxies next year, and I want to have some knowledge about it and about what is going on, before my lessons so i dont go there with no idea.A good explanation would be greatly appreciated!So please help if u can! Thanx alot in advance!! <br /> Posted by 5attab</DIV></p><p>http://en.wikipedia.org/wiki/Metric_expansion_of_space</p><p>http://en.wikipedia.org/wiki/Redshift</p><p>http://en.wikipedia.org/wiki/Age_of_the_universe</p><p>&nbsp;</p><p>These three links should get you started.&nbsp; Any questions, feel free to ask.&nbsp;</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[5attab]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>http://en.wikipedia.org/wiki/Metric_expansion_of_spacehttp://en.wikipedia.org/wiki/Redshifthttp://en.wikipedia.org/wiki/Age_of_the_universeThese three links should get you started.&nbsp; Any questions, feel free to ask.&nbsp; <br /> Posted by derekmcd</DIV></p><p>I dont get how galaxies moving apart is related to the expansion of space? </p>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I dont get how galaxies moving apart is related to the expansion of space? <br />Posted by 5attab</DIV><br />&nbsp;</p><p>Try this analogy. It is actually pretty close.&nbsp; Take a balloon and inflate it slightly.&nbsp; Now take a ballpoint pen and put a few dots on the balloon.&nbsp; Now inflate the balloon fully.&nbsp; Notice that as the balloon inflates (like space expanding) that the dots (galaxies) become farther apart.&nbsp; Notice also that rate at which one dot recedes from another is proportional to how far apart they are.&nbsp; Notice also that there is no central point, on the balloon, for this expansion.&nbsp; All points recede from one another and all see essentially the same thing from their perspective.&nbsp; There is no preferred point.&nbsp; Note also that from the perspective of any single point all other points appear to be moving directly away from that point.&nbsp; </p> <div class="Discussion_UserSignature"> </div>

 

[derekmcd]

<p>Just keep in mind with the balloon analogy that there is no inside or outside of the balloon.&nbsp; You should only consider the surface of the balloon as our entire universe.&nbsp; The surface of the balloon is analogous to our 3 dimenssional space.&nbsp;</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[5attab]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;Try this analogy. It is actually pretty close.&nbsp; Take a balloon and inflate it slightly.&nbsp; Now take a ballpoint pen and put a few dots on the balloon.&nbsp; Now inflate the balloon fully.&nbsp; Notice that as the balloon inflates (like space expanding) that the dots (galaxies) become farther apart.&nbsp; Notice also that rate at which one dot recedes from another is proportional to how far apart they are.&nbsp; Notice also that there is no central point, on the balloon, for this expansion.&nbsp; All points recede from one another and all see essentially the same thing from their perspective.&nbsp; There is no preferred point.&nbsp; Note also that from the perspective of any single point all other points appear to be moving directly away from that point.&nbsp; <br /> Posted by DrRocket</DIV></p><p>Thank you very much for the explanation and the good example! </p>

 

[BoJangles]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I dont get how galaxies moving apart is related to the expansion of space? <br />Posted by 5attab</DIV></p><p>Google video is a great resource for relaxed learning</p><p>Try these, i watch things like this in the background while im doing other things</p><p>Although these are fairly basic they are a great place to start</p><p>Dark Energy and the Runaway Universe<br />http://video.google.com.au/videoplay?docid=-4829822453816613715&q=alex+filippenko&ei=BwiISLjoN4WmrgO5ipnOCA&hl=en</p><p>Sam Neil has a great doco as well.&nbsp;A good starter</p><p><u><font color="#810081">http://www.youtube.com/watch?v=a-ngsgxhGS0&feature=related</font></u>http://www.youtube.com/watch?v=a-ngsgxhGS0</p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <p align="center"><font color="#808080">-------------- </font></p><p align="center"><font size="1" color="#808080"><em>Let me start out with the standard disclaimer ... I am an idiot, I know almost nothing, I haven’t taken calculus, I don’t work for NASA, and I am one-quarter Bulgarian sheep dog.  With that out of the way, I have several stupid questions... </em></font></p><p align="center"><font size="1" color="#808080"><em>*** A few months blogging can save a few hours in research ***</em></font></p> </div>

 

[5attab]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Google video is a great resource for relaxed learningTry these, i watch things like this in the background while im doing other thingsAlthough these are fairly basic they are a great place to startDark Energy and the Runaway Universehttp://video.google.com.au/videoplay?docid=-4829822453816613715&q=alex+filippenko&ei=BwiISLjoN4WmrgO5ipnOCA&hl=enSam Neil has a great doco as well.&nbsp;A good starterhttp://www.youtube.com/watch?v=a-ngsgxhGS0&feature=related <br /> Posted by Manwh0re</DIV></p><p>Awesome!</p><p>I sure will check them out! exactly what i wanted somthing simple to start with <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-laughing.gif" border="0" alt="Laughing" title="Laughing" /></p><p>I found the wikipedia articles quite hard to understand, as i havent learned a thing about astronomy in my life. So thanx alot!! <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-wink.gif" border="0" alt="Wink" title="Wink" /> </p>

 

[Wolf873]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Google video is a great resource for relaxed learningTry these, i watch things like this in the background while im doing other thingsAlthough these are fairly basic they are a great place to startDark Energy and the Runaway Universehttp://video.google.com.au/videoplay?docid=-4829822453816613715&q=alex+filippenko&ei=BwiISLjoN4WmrgO5ipnOCA&hl=enSam Neil has a great doco as well.&nbsp;A good starterhttp://www.youtube.com/watch?v=a-ngsgxhGS0&feature=related <br /> Posted by Manwh0re</DIV></p><p>&nbsp;</p><p>That is an excellent Documentary by Sam Neil, it really taught me alot.&nbsp;</p> <div class="Discussion_UserSignature"> <font size="2" color="#3366ff"><em>The most merciful thing in this world is the human mind's inability to correlate all its contents.</em></font> </div>

 

[derekmcd]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Awesome!I sure will check them out! exactly what i wanted somthing simple to start with I found the wikipedia articles quite hard to understand, as i havent learned a thing about astronomy in my life. So thanx alot!! <br /> Posted by 5attab</DIV></p><p>The best way to understand something is to ask questions.&nbsp; Fire away!!! <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-laughing.gif" border="0" alt="Laughing" title="Laughing" /> </p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[baulten]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Just keep in mind with the balloon analogy that there is no inside or outside of the balloon.&nbsp; You should only consider the surface of the balloon as our entire universe.&nbsp; The surface of the balloon is analogous to our 3 dimenssional space.&nbsp; <br /> Posted by derekmcd</DIV></p><p>Well, you can consider the inside of the balloon the past and the oustide the future and get a pretty decent idea of how expansion compares to time.&nbsp; It's not a spacial dimension (in and out of the balloon that is), it's a time dimension. </p>

 

[derekmcd]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Well, you can consider the inside of the balloon the past and the oustide the future and get a pretty decent idea of how expansion compares to time.&nbsp; It's not a spacial dimension (in and out of the balloon that is), it's a time dimension. <br /> Posted by baulten</DIV></p><p>I've used that analogy many times, but I don't refer to it as a dimension.&nbsp; It's more applicable when considering the age.&nbsp; Time, when considered as a dimension, is more relavent to events within the 3 dimensional space. </p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[5attab]

<p>btw, does anyone have other sites that provide info that is simpler and easier to understand than wikipedia? im finding wikipedia quite complicated tbh.</p><p>thanx. </p>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>btw, does anyone have other sites that provide info that is simpler and easier to understand than wikipedia? im finding wikipedia quite complicated tbh.thanx. <br />Posted by 5attab</DIV></p><p>Here are a few books that are written by experts for the general public.&nbsp; They require very little math.</p><p>A Brief History of Time -- Stephen Hawking</p><p>Black Holes and Timewarps; Einstein's Outrageous Legacy -- Kip Thorne</p><p>The Inflationary Universe -- Alan Guth</p><p>The Elegant Universe -- Brian Greene</p><p>The Fabric of the Cosmos -- Brian Greene</p><p>The&nbsp;next one is a bit more demanding, but Roger Penrose is about as smart and knowledgeable as they come</p><p>The Road to Reality -- Roger Penrose<br /></p> <div class="Discussion_UserSignature"> </div>

 

[derekmcd]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>btw, does anyone have other sites that provide info that is simpler and easier to understand than wikipedia? im finding wikipedia quite complicated tbh.thanx. <br /> Posted by 5attab</DIV></p><p>I googled "basic cosmology lecture" and found this for ya:</p><p>http://www.bnl.gov/video/lectures.asp</p><p>I direct you to the 6 part lecutre titled "cosmology for beginners"</p><p>I only watched a few minutes of the first 2 lectures to check the level of "beginner" he is addressing and also to check to make sure the content is somewhat mainstream which is what I assume you are looking for.</p><p>It seems to fit what you might be looking for, but I won't vouch for the entirety of the content.&nbsp; It appears to be fairly basic and accurate.</p><p>Hope this helps ya a bit.&nbsp;</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>