Descriptions

[zarnic]

I have often either read or heard the modifiers 'seen' universe and 'known' universe. Do these imply that there is a part of our universe we can not see or don't know about? <div class="Discussion_UserSignature"> <p><em>Wisdom doesn't automatically come with old age. Nothing does - except wrinkles.</em> A. Van Buren, 1978<br />* <em>An unbreakable toy is useful for breaking other toys.</em>  -- according to Van Roy</p> </div>

 

[adrenalynn]

I believe what's happening there is leaving room open for what we can't see and don't know.<br /><br />Even the resolution of what we can see is trivial. That, of course, improves daily - such as the advances in adaptive optics (and maybe someday, adaptive high-spectrum, like XRay and Gamma).<br /><br />There's a lot going on out there in the universe that we can't see [yet]. <div class="Discussion_UserSignature"> <p>.</p><p><font size="3">bipartisan</font>  (<span style="color:blue" class="pointer"><span class="pron"><font face="Lucida Sans Unicode" size="2">bī-pär'tĭ-zən, -sən</font></span></span>) [Adj.]  Maintaining the ability to blame republications when your stimulus plan proves to be a devastating failure.</p><p><strong><font color="#ff0000"><font color="#ff0000">IMPE</font><font color="#c0c0c0">ACH</font> <font color="#0000ff"><font color="#c0c0c0">O</font>BAMA</font>!</font></strong></p> </div>

 

[MeteorWayne]

There are parts that we cannot see. Due to the expansion of the Universe, there are parts farther away than the light from there that could have reached us during the lifetime of the Universe.<br />We can only see a sphere about 14 billion light years across. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[zarnic]

Looks like I'm getting into the realm of Sci-Fi... thanks to you all. <div class="Discussion_UserSignature"> <p><em>Wisdom doesn't automatically come with old age. Nothing does - except wrinkles.</em> A. Van Buren, 1978<br />* <em>An unbreakable toy is useful for breaking other toys.</em>  -- according to Van Roy</p> </div>

 

[MeteorWayne]

Not at all. The question is a valid one in our Universe. While Sci Fi has addressed the issue, it certainly is a subject that belongs in this forum! <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[derekmcd]

Nothing science fiction about it. Meteorwayne is correct in the sense that we can only see objects <i>as they were</i> up to a time of 13.7gy ago. Beyond that, the universe was opaque as it was too dense for photons escape.<br /><br />I think the question you might be asking, however, is about our visible light cone and comoving distances. Don't quote my figures as I'm not referencing anything here.<br /><br />There are objects that are in their present position approx 46gly away from us that we observe as they were when they were only ~2gly in distance. These objects will remain in our light cone for a period of time until the metric expansion of space overtakes it.<br /><br />There are objects that may be some 62+gly at their current distance, but can never be observed as the comoving distance between us and them is beyond the speed of light.<br /><br />So, yes. There are object in the universe that will never be observable. <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>