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Stephen Hawking's Interstellar Spaceship Proposal (And More!)



 
 
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  #71  
Old June 7th 16, 02:51 PM posted to sci.physics,sci.astro,rec.arts.sf.science,sci.space.policy
Robert Clark[_5_]
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Default Stephen Hawking's Interstellar Spaceship Proposal (And More!)

Good question. Positronium is not an exact analogue of a hydrogen atom since
it consists of an electron and a positron (anti-electron) orbiting each
other while the hydrogen atom has an electron orbiting around the much more
massive proton. The highly advanced theory of quantum electrodynamics (QED)
mentioned in the article describes how these states are stable or unstable.

BTW, the production of antihydrogen is quite low:

CERN snags 38 antihydrogen atoms in magnetic trap.
http://arstechnica.com/science/2010/...ydrogen-atoms/
by Alexander B. Fry - Nov 17, 2010 11:11pm EST

But theoretical work may allow the production rate to be ramped up:

Physicists find ways to increase antihydrogen production.
May 20, 2015 by Lisa Zyga
http://phys.org/news/2015-05-physici...roduction.html


Bob Clark

----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it:

Nanotech: from air to space.
https://www.indiegogo.com/projects/n...ce/x/13319568/
----------------------------------------------------------------------------------------------------------------------------------
"ClutterFreak" wrote in message
...

On Sun, 29 May 2016 09:19:21 -0400, Robert Clark
wrote:

http://physicsworld.com/cws/article/...zzle-is-solved


Why same thing doesn't happend to hydrogen?
--

  #72  
Old June 7th 16, 05:44 PM posted to sci.physics,sci.astro,rec.arts.sf.science,sci.space.policy
ClutterFreak
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Default Stephen Hawking's Interstellar Spaceship Proposal (And More!)

On Tue, 7 Jun 2016 09:51:05 -0400, Robert Clark wrote:

on. Positronium is not an exact analogue of a hydrogen atom since
it consists of an electron and a positron (anti-electron) orbiting each
other while the hydrogen atom has an electron orbiting around the much more
massive proton. The highly advanced theory of quantum electrodynamics (QED)
mentioned in the article describes how these states are stable or unstable.


So the difference is made only by higher mass where
the positive charge is, something as lame as just
gravity at that scale, or is it much more involved
having to do with what "mass" itself is?
--
"Woade Hueoo"
-extra thick-lipped Black American female
intending to say "Walnut Hill"

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  #73  
Old June 7th 16, 06:57 PM posted to sci.physics,sci.astro,rec.arts.sf.science,sci.space.policy
Sea Wasp (Ryk E. Spoor)
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Posts: 127
Default Stephen Hawking's Interstellar Spaceship Proposal (And More!)

On 6/7/16 9:51 AM, Robert Clark wrote:
Good question. Positronium is not an exact analogue of a hydrogen atom
since it consists of an electron and a positron (anti-electron) orbiting
each other while the hydrogen atom has an electron orbiting around the
much more massive proton.


So why isn't it made of a positron in orbit around an anti-proton? That
would be an exact analogue, yes?


--
Sea Wasp
/^\
;;;
Website: http://www.grandcentralarena.com Blog:
http://seawasp.livejournal.com

  #74  
Old June 7th 16, 07:09 PM posted to sci.physics,rec.arts.sf.science,sci.astro,sci.space.policy
Robert Clark[_5_]
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Posts: 245
Default Stephen Hawking's Interstellar Spaceship Proposal (And More!)

DARPA is funding methods of getting separate components to self-assemble and
form larger satellites and also self-assemble to form robotic rovers:

How Tiny 'SuperBots' Will Create Cheap, Modular Satellites.
BY SOPHIA STUART JANUARY 14, 2015 1 COMMENT
http://www.pcmag.com/article2/0,2817,2475070,00.asp

Bob Clark



----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it:

Nanotech: from air to space.
https://www.indiegogo.com/projects/n...ce/x/13319568/
----------------------------------------------------------------------------------------------------------------------------------
"Robert Clark" wrote in message ...

You may be thinking of self-reproducing which is different from
self-assembly. Self-assembly can be done at the macroscale. Considering the
advances in nanoscale devices it should be doable at the nanoscale.

Bob Clark

----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it:

Nanotech: from air to space.
https://www.indiegogo.com/projects/n...ce/x/13319568/
----------------------------------------------------------------------------------------------------------------------------------
"Sjouke Burry" wrote in message
...

On 22.05.16 22:48, Robert Clark wrote:

Suppose we made the probes at the virus or bacteria scale then used
self-assembly to form a macroscale spacecraft say size of Mars Pathfinder.
Then we might only need a ground laser of currently existing size, say a
few
hundred kilowatts, to send multiple nanoscale components to relativistic
speeds.

Know of references for doing self-assembly with components at the
nanoscale?

Bob Clark



You think that you can put a computer/assembly line inside
a nano particle?
Please show us how.
It should be able to go after raw material in space,which
needs oodles of energy.
What useful amount of energy can you store in a nano particle?
Where does the particle get the ions to to travel millions of miles?

I think a minimal self-reproducing craft would weight several tons,
and be anything but small.

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  #75  
Old June 7th 16, 08:33 PM posted to sci.space.policy,sci.astro,sci.physics,rec.arts.sf.science
Duster Zee
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Posts: 1
Default Stephen Hawking's Interstellar Spaceship Proposal (And More!)

Alain Fournier wrote:
On May/22/2016 at 4:48 PM, Robert Clark wrote :

Suppose we made the probes at the virus or bacteria scale then used
self-assembly to form a macroscale spacecraft say size of Mars
Pathfinder. Then we might only need a ground laser of currently existing
size, say a few hundred kilowatts, to send multiple nanoscale components
to relativistic speeds.

Know of references for doing self-assembly with components at the
nanoscale?


As others have mentioned, this kind of self-assembly is rather far-out
in the sci-fi zone. But even if you did have such self assembly,
focusing your laser on something far away that is of nanometric size
is yet another challenge far-out in the sci-fi zone.


Alain Fournier

------------------------------------------
Those guys have too much money.

Imagine looking at a planet which is 1400 light years away,
a place where any member of the human race can never be,
no matter how long he has to do it.

DZ




  #76  
Old June 7th 16, 09:07 PM posted to sci.physics,sci.astro,rec.arts.sf.science,sci.space.policy
Robert Clark[_5_]
external usenet poster
 
Posts: 245
Default Stephen Hawking's Interstellar Spaceship Proposal (And More!)

Yes. In the post earlier today in this thread I discussed antihydrogen being
formed.

Bob Clark


----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it:

Nanotech: from air to space.
https://www.indiegogo.com/projects/n...ce/x/13319568/
----------------------------------------------------------------------------------------------------------------------------------
"Sea Wasp (Ryk E. Spoor)" wrote in message
...

On 6/7/16 9:51 AM, Robert Clark wrote:
Good question. Positronium is not an exact analogue of a hydrogen atom
since it consists of an electron and a positron (anti-electron) orbiting
each other while the hydrogen atom has an electron orbiting around the
much more massive proton.


So why isn't it made of a positron in orbit around an anti-proton? That
would be an exact analogue, yes?
--
Sea Wasp
/^\
;;;
Website: http://www.grandcentralarena.com Blog:
http://seawasp.livejournal.com
---

 




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