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A comment on How Big is Space?.

Re:How Big is Space? by curiousjorge on Tuesday July 14, 2015 @04:33PM (#9887839)
Kinda depressing just how small we are and that we can't get around places to explore space without some groundbreaking invention that will transfer information from the atoms to another location instantly (something like spooky action except that after you are finished copying the atom data, the old copy must be deleted to prevent endless dopplegangers appearing) by appending some complex 3d position information (move all of my atom by appending some coordinates that could never be reached with even light travel). Something like http://hansonlab.tudelft.nl/teleportation/
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Re:How Big is Space? by sktrdie on Tuesday July 14, 2015 @04:55PM (#9888000)
I just can't help but think that we'll reach a wall when it comes to exploring the real world. Even if we get to travel at the speed of light, we're still limited by it. In 20 years of light travel we'd only visit relatively close clusters. All the other stuff is thousands of light years away. Not to mention exploring other galaxies which are millions of light years away.

Quality of life in the virtual world will perhaps be better than that of the real world. In fact, this is my explanation for the fermi paradox. Most aliens out there have essentially "given up" the idea of exploring because everything is just too far away and they simply can't bend the rules of physics. So they're all living in the matrix.

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Re:How Big is Space? by marcosscriven on Tuesday July 14, 2015 @05:20PM (#9888137)
With time-dilation, from the point of view of those on board, it's actually possible to travel as far as Andromeda with constant 1g acceleration (decelerating at 1g half way), within a few decades. Of course, time back on earth would have gone by a few million years...
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Re:How Big is Space? by sktrdie on Tuesday July 14, 2015 @05:34PM (#9888223)
Huh, but if light takes 2.5 million years to get to Andromeda, how does it take us a few decades? You're saying that from the point of view of the photon, it takes much less time?
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Re:How Big is Space? by Guillaume86 on Tuesday July 14, 2015 @05:41PM (#9888257)
Yes photons do not experience time, it's all the same instant for them
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Re:How Big is Space? by sktrdie on Tuesday July 14, 2015 @06:16PM (#9888439)
So a photon can get anywhere it wants instantly to them?
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Re:How Big is Space? by mahranch on Tuesday July 14, 2015 @08:23PM (#9888989)
This is a great article (for laypeople, it's not supposed to be too technical) that explains it and makes it easy to understand: http://zidbits.com/2011/04/why-cant-anything-go-faster-than-...

I'll quote the relevant bit, "Imagine for a moment that you are a happy little photon created by a star in another galaxy some 4 billion light years away. From my perspective here on Earth, it took you exactly 4 billion years to travel from that star till you reached my retina. From your perspective, one instant you were created and then the next, you are are bouncing off or being absorbed by my eyeball. You experienced no passage of time. Your birth and death happened instantaneously.

This is because time slows for you as your get closer to light speed, and at it, it completely stops. This is also another reason why nothing can go faster than light. It would be like slowing down a car to a stop, and then trying to go slower than completely stopped."

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Re:How Big is Space? by svalorzen on Wednesday July 15, 2015 @04:20AM (#9890272)
Not only this, but due to space compression to the photon the star and your eye are also exactly the same place!
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Re:How Big is Space? by perfTerm on Tuesday July 14, 2015 @10:08PM (#9889327)
It's super interesting that the speed of light is exactly 282,xyz (can't remember) miles per second. What're the chances? I'm just unable to comprehend the idea that a fundamental universal constant could be an exact whole number amount of an arbitrary measurement unit like that. You'd think there'd be a few decimal points or something.
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Re:How Big is Space? by whopa on Tuesday July 14, 2015 @11:27PM (#9889545)
You're misremembering. The speed of light in miles per second is ~186,282.396. The speed of light in meters per second is 299,792,458, but the meter is defined using the speed of light:

https://en.wikipedia.org/wiki/Speed_of_light

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Re:How Big is Space? by koverstreet on Tuesday July 14, 2015 @07:42PM (#9888843)
From the reference fram of the photon, yes
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Re:How Big is Space? by mkehrt on Tuesday July 14, 2015 @05:42PM (#9888263)
Yes, that's how relativity works.
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Re:How Big is Space? by mirimir on Wednesday July 15, 2015 @02:40AM (#9890027)
Plus, as in Egan's Diaspora, virtual entities can hibernate, or live at far lower clock frequency.
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Re:How Big is Space? by ttrmw on Wednesday July 15, 2015 @07:18AM (#9890718)
I've not read Diaspora (yet!), but this sounds more like Permutation City
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Re:How Big is Space? by mirimir on Wednesday July 15, 2015 @08:08AM (#9890859)
I haven't read Permutation City yet, but virtualization in Diaspora is far more advanced. The default, as I recall, is ~800 times meatspace. I recommend reading Stephenson's Anathem first, however.

Edit: The Planck Dive is a follow-on.[0]

[0] http://gregegan.customer.netspace.net.au/PLANCK/Complete/Pla...

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Re:How Big is Space? by curiousjorge on Tuesday July 14, 2015 @07:13PM (#9888702)
Fermi paradox is interesting because if aliens did have the ability to teleport they would've done so. The matrix does sound reasonable. What if we could have everything in this virtual world? The argument that we are in a matrix right now is moot because it kinda sucks. Great for the 1 percenters tho.
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Re:How Big is Space? by XzetaU8 on Wednesday July 15, 2015 @07:38AM (#9890773)
There are already plenty "solutions" for the Fermi paradox, one of those is the Multiverse hypothesis https://en.wikipedia.org/wiki/Multiverse another one is the Holographic principle http://motherboard.vice.com/read/there-is-growing-evidence-t...
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Re:How Big is Space? by danhsh on Tuesday July 14, 2015 @07:34PM (#9888802)
what if . we invent a way to not reach out, but however reduce the space, that is how einstein will think.
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Re:How Big is Space? by dghf on Wednesday July 15, 2015 @06:20AM (#9890561)
> Kinda depressing just how small we are and that we can't get around places to explore space without some groundbreaking invention that will transfer information from the atoms to another location instantly

If that ever happens, you'd better hope that the Novikov self-consistency principle [0] holds, or be ready to deal with the inevitable causality violations.[1]

[0] https://en.wikipedia.org/wiki/Novikov_self-consistency_princ...

[1] http://www.askamathematician.com/2012/07/q-how-does-instanta...

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Re:How Big is Space? by thaumasiotes on Tuesday July 14, 2015 @04:39PM (#9887883)
> after you are finished copying the atom data, the old copy must be deleted to prevent endless dopp[el]gangers appearing

Why would we need to prevent this?

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Re:How Big is Space? by curiousjorge on Tuesday July 14, 2015 @07:05PM (#9888663)
Well when you want to comeback home , you don't want to come across a clone of yourself who already married your lover, had kids, settled down and your ex lover says "you were never around what did you expect and besides it's not like I'm cheating on you because it's a copy of you". I'd imagine time travels faster when you are out exploring deep space and having a blast while the copy of you is living his life on earth. Yeah, still worth it.
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Re:How Big is Space? by pixl97 on Wednesday July 15, 2015 @08:48AM (#9890976)
The Agent Smith problem. Right now if an entity in meatspace wants to copy itself it has to breed, and for anything complex the copies are not the same and have to go through a growing process. With copy teleportation it's not really any different than Ctrl+C/Ctrl+V on your computer. As long as you have the energy you can build entire armies of yourself. There many be plenty of good scenarios for this to happen but I can think of far more downsides.
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Re:How Big is Space? by keedot on Tuesday July 14, 2015 @04:44PM (#9887913)
Play Sims 4 with the "Get to work" expansion. Having 8 me's in a house is a real problem.
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