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BBC NEWS | Technology | Robots that climb walls - 0 views

news.bbc.co.uk/...7494974.stm Robotics robots

shared by ESA ACT on 24 Apr 09 - Cached

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Dark Matter or Black Hole Propulsion? - 1 views

www.newscientist.com/...s-for-interstellar-travel.html NRG propulsion star travel space PHY

shared by Ma Ru on 25 Nov 09 - Cached

Ma Ru on 25 Nov 09

Anyone out there still doing propulsion stuff? Two more papers just waiting to get busted... http://arxiv.org/abs/0908.1429v1 http://arxiv.org/abs/0908.1803

<div class="cArrow"> </div><div class="cContentInner">Anyone out there still doing propulsion stuff? Two more papers just waiting to get busted... <a href="http://arxiv.org/abs/0908.1429v1" rel="nofollow" target="_blank">http://arxiv.org/abs/0908.1429v1</a> <a href="http://arxiv.org/abs/0908.1803" rel="nofollow" target="_blank">http://arxiv.org/abs/0908.1803</a></div>

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...5 more comments...
Luzi Bergamin on 26 Nov 09

What an awful bunch of complete nonsense!!! But I don't think anybody wants to hear MY opinion on this...

<div class="cArrow"> </div><div class="cContentInner">What an awful bunch of complete nonsense!!! But I don't think anybody wants to hear MY opinion on this...</div>

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pacome delva on 26 Nov 09

wow, is this serious at all...!?

<div class="cArrow"> </div><div class="cContentInner">wow, is this serious at all...!?</div>

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Luzi Bergamin on 26 Nov 09

Are you joking?? The BH drive propses a BH with a lifetime of about an year, just 10^7 tons, peanuts!! Then you have to produce it, better not on Earth, so you do this in space, with a laser that produces an equivalent of 10^9 tons highly foucussed, even more peanuts!! Reasonable losses in the production process (probably 99,999%) are not yet taken into account. Engineering problems... :-) The DM drive is even better, they want to collect DM and compress it in a propulsion chamber. Very easy to collect and compress a gas of particles that traverse the Earth without any interaction. Perhaps if the walls of the chamber are made of artificial BHs?? Who knows??

<div class="cArrow"> </div><div class="cContentInner">Are you joking?? The BH drive propses a BH with a lifetime of about an year, just 10^7 tons, peanuts!! Then you have to produce it, better not on Earth, so you do this in space, with a laser that produces an equivalent of 10^9 tons highly foucussed, even more peanuts!! Reasonable losses in the production process (probably 99,999%) are not yet taken into account. Engineering problems... :-) The DM drive is even better, they want to collect DM and compress it in a propulsion chamber. Very easy to collect and compress a gas of particles that traverse the Earth without any interaction. Perhaps if the walls of the chamber are made of artificial BHs?? Who knows??</div>

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LeopoldS on 26 Nov 09

WRONG!!! we are all just WAITING for your opinion on this ....!!!

<div class="cArrow"> </div><div class="cContentInner">WRONG!!! we are all just WAITING for your opinion on this ....!!!</div>

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pacome delva on 27 Nov 09

well, yes my remark was ironic... I'm surprised they did a magazine on these concepts...! But the press is always waiting for sensational. They do not even wait for the work to be peer-reviewed now to make an article on it ! This is one of the bad sides of arxiv in my opinion. It's like a journalist that make an article with a copy-paste in wikipedia ! Anyway, this is of course complete bullsh..., and I would have laughed if I had read this in a sci-fi book... but in a "serious" article i'm crying... For the DM i do not agree with your remark Luzi. It's not dark energy they want to use. The DM is baryonic, it's dark just because it's cold so we don't see it by usual means. If you believe the in the standard model of cosmology, then the DM should be somewhere around the galaxies. But it's of course not uniformly distributed, so a DM engine would work (if at all...) only in the periphery of galaxies. It's already impossible to get there...

<div class="cArrow"> </div><div class="cContentInner">well, yes my remark was ironic... I'm surprised they did a magazine on these concepts...! But the press is always waiting for sensational. They do not even wait for the work to be peer-reviewed now to make an article on it ! This is one of the bad sides of arxiv in my opinion. It's like a journalist that make an article with a copy-paste in wikipedia ! Anyway, this is of course complete bullsh..., and I would have laughed if I had read this in a sci-fi book... but in a "serious" article i'm crying... For the DM i do not agree with your remark Luzi. It's not dark energy they want to use. The DM is baryonic, it's dark just because it's cold so we don't see it by usual means. If you believe the in the standard model of cosmology, then the DM should be somewhere around the galaxies. But it's of course not uniformly distributed, so a DM engine would work (if at all...) only in the periphery of galaxies. It's already impossible to get there...</div>

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Luzi Bergamin on 27 Nov 09

One reply to Pacome, though the discussion exceeds by far the relevance of the topic already. Baryonic DM is strictly limited by cosomology, if one believes in these models, of course. Anyway, even though most DM is cold, we are constantly bombarded by some DM particles that come together with cosmic radiation, solar wind etc. etc. If DM easily interacted with normal matter, we would have found it long ago. In the paper they consider DM as neutralinos, which are neither baryonic nor strongly or electromagnetically interacting.

<div class="cArrow"> </div><div class="cContentInner">One reply to Pacome, though the discussion exceeds by far the relevance of the topic already. Baryonic DM is strictly limited by cosomology, if one believes in these models, of course. Anyway, even though most DM is cold, we are constantly bombarded by some DM particles that come together with cosmic radiation, solar wind etc. etc. If DM easily interacted with normal matter, we would have found it long ago. In the paper they consider DM as neutralinos, which are neither baryonic nor strongly or electromagnetically interacting.</div>

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pacome delva on 27 Nov 09

well then I agree, how the fu.. they want to collect them !!!

<div class="cArrow"> </div><div class="cContentInner">well then I agree, how the fu.. they want to collect them !!!</div>

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Google plans for internet from space with 180 LEO satellites - 2 views

www.engadget.com/...gle-making-internet-satellites technology google space

shared by Thijs Versloot on 02 Jun 14 - No Cached

LeopoldS and johannessimon81 liked it

Thijs Versloot on 02 Jun 14

The Wall Street Journal hears that the search firm is preparing to build 180 "small, high capacity" satellites that will go into low orbit and provide internet connections to underserved areas

<div class="cArrow"> </div><div class="cContentInner">The Wall Street Journal hears that the search firm is preparing to build 180 "small, high capacity" satellites that will go into low orbit and provide internet connections to underserved areas</div>

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LeopoldS on 02 Jun 14

sorry, did not see your earlier post ... fully altruistic move of course as they claim

<div class="cArrow"> </div><div class="cContentInner">sorry, did not see your earlier post ... fully altruistic move of course as they claim</div>

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Nicholas Lan on 04 Jun 14

actually I posted about it first :P

<div class="cArrow"> </div><div class="cContentInner">actually I posted about it first :P</div>

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