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Old 06-16-2008   #111 (permalink)
Moontanman's Avatar
Astounding Vision


 



Re: Terraforming Mars

Quote:

I prefer abiogenesis, but I do not completely discount exogenesis. This does not mean that I believe in a supernatural creator. I prefer exogenesis to panspermia for this reason.
I have to ask, how is exogenesis any different than abiogenesis or panspermia? I really am not clear on these three if there is any real difference.

Quote:
I wholeheartedly agree!
[/quote]

Me too.


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Michael
Life is the poetry of the universe.
Love is the poetry of life.

Nuclear is the only real option!
http://www.nuclearspace.com/Liberty_ship_menupg.aspx

Check this out
http://www.conservationfisheries.org...ream_lines.htm

Over heard from a three year old, "Daddy why do my toes get sticky when I eat strawberry jam?"

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Old 06-17-2008   #112 (permalink)
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Post Nimtz and Stahlhofen’s FTL signaling experiment

Quote:
Originally Posted by dcmike View Post
It was indelibly engraved in stone tablets that nothing can go faster than the speed of light - but a German professor proved that wrong by sending and then retreiving data (intact) at nearly five times the speed of light. That opens up the possibility of some sort of time travel - even if only retrieval of information.
Quote:
Originally Posted by Moontanman View Post
I'm tired of this discussion, do you have a link to this experiment, I would like to read about this.
We’ve discussed the experiment in frustrated total internal reflection and quantum tunneling described in Nimtz and Stahlhofen’s 2007 paper “Macroscopic violation of special relativity” in threads ”We have broken speed of light”,
”FTL signaling via frustrated total internal reflection”, and, most in-depth, I think, around post ”A theoretical way to communicate FTL/back in time & an additional Clarke-esque law” of thread “FTL Communication”. The wikipedia article “Günter Nimtz” also has a brief description of the experiment and various responses to it.

Assuming, as one may from the paper’s Feynman diagram (Figure 2) that the tunneling time is actually zero, the actual speed of the signal is v = \frac{a+b}{an} c, where a is the total light path length through the prisms, b is the gap between them, n is the refractive index of their material, and c the speed of light in vacuum.

The paper gives n=1.6 and (indirectly) a = 0.2 \,\mbox{m}, from which we can calculate that v > c when b > 0.24 \,\mbox{m}. The paper does not describe b, other than indirectly in the Figure 1 illustration, where it appears to be about 0.1 m, a distance that would not result in a signal speed greater than c. The wikipedia article “Günter Nimtz” states
Photons can be detected behind the prisma at the right side until the gap exceeds approx. one meter
, which would.

Clearly, an authoritative value for b is critical for the reader to determining whether the experiment demonstrates actual FTL signaling. I find the lack of such data, and of experimental verification by other scientists, suspicious and disturbing

In short, and in my opinion, the FTL effect illustrated and measured in Nimtz and Stahlhofen’s experiment are not prohibited by physical law. The apparent contradiction between special relativity, which prohibits FTL signaling by postulate, and quantum electrodynamic, which does not, is removed by the observation that SR is a classical, not a quantum mechanical, theory. However, QM typically assumes that macroscopic effects are statistically bound to the postulates of relativity, leaving me uncertain of the implications of the described effect.

I’ll started a thread “Is Nimtz and Stahlhofen’s FTL signaling for real?”, to discuss these questions, soon. I’ll also split this thread as necessary to keep it on its original topic, while not losing its many off-topic posts.


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Old 06-17-2008   #113 (permalink)
Moontanman's Avatar
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Re: Nimtz and Stahlhofen’s FTL signaling experiment

Quote:
Originally Posted by CraigD View Post
We’ve discussed the experiment in frustrated total internal reflection and quantum tunneling described in Nimtz and Stahlhofen’s 2007 paper “Macroscopic violation of special relativity” in threads ”We have broken speed of light”,
”FTL signaling via frustrated total internal reflection”, and, most in-depth, I think, around post ”A theoretical way to communicate FTL/back in time & an additional Clarke-esque law” of thread “FTL Communication”. The wikipedia article “Günter Nimtz” also has a brief description of the experiment and various responses to it.

Assuming, as one may from the paper’s Feynman diagram (Figure 2) that the tunneling time is actually zero, the actual speed of the signal is v = frac{a+b}{an} c, where a is the total light path length through the prisms, b is the gap between them, n is the refractive index of their material, and c the speed of light in vacuum.

The paper gives n=1.6 and (indirectly) a = 0.2 ,mbox{m}, from which we can calculate that v > c when b > 0.24 ,mbox{m}. The paper does not describe b, other than indirectly in the Figure 1 illustration, where it appears to be about 0.1 m, a distance that would not result in a signal speed greater than c. The wikipedia article “Günter Nimtz” states
Photons can be detected behind the prisma at the right side until the gap exceeds approx. one meter
, which would.

Clearly, an authoritative value for b is critical for the reader to determining whether the experiment demonstrates actual FTL signaling. I find the lack of such data, and of experimental verification by other scientists, suspicious and disturbing

In short, and in my opinion, the FTL effect illustrated and measured in Nimtz and Stahlhofen’s experiment are not prohibited by physical law. The apparent contradiction between special relativity, which prohibits FTL signaling by postulate, and quantum electrodynamic, which does not, is removed by the observation that SR is a classical, not a quantum mechanical, theory. However, QM typically assumes that macroscopic effects are statistically bound to the postulates of relativity, leaving me uncertain of the implications of the described effect.

I’ll started a thread “Is Nimtz and Stahlhofen’s FTL signaling for real?”, to discuss these questions, soon. I’ll also split this thread as necessary to keep it on its original topic, while not losing its many off-topic posts.
Splitting this thread is a good idea, I think it has already been split more than once and I would not want to see many of the thread lost. I would like to follow up on the FTL signaling at some point. It is bad that such claims are often made of violating some premise and then not followed up and the idea is often used far outside it's context with out question.


----------------
Michael
Life is the poetry of the universe.
Love is the poetry of life.

Nuclear is the only real option!
http://www.nuclearspace.com/Liberty_ship_menupg.aspx

Check this out
http://www.conservationfisheries.org...ream_lines.htm

Over heard from a three year old, "Daddy why do my toes get sticky when I eat strawberry jam?"

Never wrestle a troll. You both get dirty and the troll likes it

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Old 06-25-2008   #114 (permalink)
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Re: Terraforming Mars

"............a German professor proved that wrong by sending and then retreiving data (intact) at nearly five times the speed of light."

"....I'm tired of this discussion, do you have a link to this experiment"

__________________________________________________ __

I think everybody is tired of this discussion! I provided a link but that is not the point now. At this point it is not a scholarly debate but a game of primordial dominance (like one male dog trying to hump another male dog to retain rank). My original remark was (MOL) "what if we terra formed mars and an organism (very resilient but rendered dormant by formerly extremely harsh conditions) emerged, invigorated by more favorable conditions, to be extremely virulent to humans".

The only intelligent answer would be "what a drag - if it happened!!" Since we are not in possession of all knowledge of all variables of all possibilities of all variations of all life forms in the entire universe we can not say with authority what can or can not not possibly occur in the rare incidence.

Out of respect to Freeztar (a moderator here) I withdraw from this melee. It was originally relevant (merely as a sidebar) to terra forming Mars, but now all serious contenders (self included) appear to withdraw from further posturing.

I only engage in discussions like this to learn, and so far all I have learned from this and other various groups (of varied subject matters) is the majority of posts are made by ego deprived megalomaniacs who are out to show off. I have yet to find a discussion group dominated by "discussers". How boring is monotonous predictability.

To all serious, scholorly posters - you are not included in my diatribe

Last edited by dcmike; 06-25-2008 at 06:00 PM. Reason: disclaimer
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Old 1 Week Ago   #115 (permalink)
belovelife's Avatar
Questioning


 



Re: Terraforming Mars

i just read that some mushrooms are tough in the presence of radiation and actually grow better

i also threw up a theory
have you put aluminum foil in the microwave
bad idea right
but why
it creates plasma that can find its way to ground via wires(the energy that causes the plasma)
so if we took a ton of solar pannels, put them in space orbiting mars
shot a highly focused microwave beam
to dishes on the surface
not only would we power any facilities we had there
we wold also warm the atmoshere

now as far as getting that magnetic field
remember in elementary school
when you took the magnet and rubbed the scissors
well if we gathered enough material from say the asteroid in N.E.O.
status and other debrit from the asteroid belt and created a moon
then mabe we could induce a magnetic field
thats my lineof thought on the subject
either that or have hundreds of strong solar powered elctro magnets orbiting the planet with the main purpose of creating an artificial magnetic field


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Old 1 Week Ago   #116 (permalink)
Moontanman's Avatar
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Re: Nimtz and Stahlhofen’s FTL signaling experiment

Quote:
Originally Posted by CraigD View Post
I’ll started a thread “Is Nimtz and Stahlhofen’s FTL signaling for real?”, to discuss these questions, soon. I’ll also split this thread as necessary to keep it on its original topic, while not losing its many off-topic posts.
Craig, did you ever start this thread?


----------------
Michael
Life is the poetry of the universe.
Love is the poetry of life.

Nuclear is the only real option!
http://www.nuclearspace.com/Liberty_ship_menupg.aspx

Check this out
http://www.conservationfisheries.org...ream_lines.htm

Over heard from a three year old, "Daddy why do my toes get sticky when I eat strawberry jam?"

Never wrestle a troll. You both get dirty and the troll likes it

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Old 1 Week Ago   #117 (permalink)
belovelife's Avatar
Questioning


 



Re: Terraforming Mars

on the travel to mars thing
with the orion rocket series
there is a plan to send an unmanned one first
with hydrogen onboard
then when it lands
it is sopposed to convert the co2+2(H2) ->CH4+O2
FOR THE RETURN FLIGHT HOME
basically methane rocket fuel
and when the lander comes
they should be able to put the methane production plant in their module
fly home while more fuel is created for the next mission


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Old 1 Week Ago   #118 (permalink)
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Re: Terraforming Mars

although i'm not a chem major
is there more potential energy in hydrogen peroxide
HO+H=H2O
per volumetric ratio?
i'm sure someone has the calculation


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Old 1 Week Ago   #119 (permalink)
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Re: Nimtz and Stahlhofen’s FTL signaling experiment

Quote:
Originally Posted by Moontanman View Post
Quote:
Originally Posted by CraigD View Post
I’ll started a thread “Is Nimtz and Stahlhofen’s FTL signaling for real?”, to discuss these questions, soon. I’ll also split this thread as necessary to keep it on its original topic, while not losing its many off-topic posts.
Craig, did you ever start this thread?Craig, did you ever start this thread?
No, so please feel free to start it for us.

I think Nimitz and Stahlhofen’s experiment has profound implications, which are being under-discussed at hypography, the greater science enthusiast community, and even academic and commercial science. Even if, as at least two papers (Herbert G. Winful’s 'Comment on “Macroscopic violation of special relativity” by Nimtz and Stahlhofen' and Chris Lee’s 'Latest "faster than the speed of light" claims wrong (again)') state, Himitz and Stahlhofen's claims are wrong (or “worse than wrong”), they're still both interesting and, I think, important.


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Old 1 Week Ago   #120 (permalink)
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Post H2O2 monofuel vs H+O bifuel vs. H+H2O2 bifuel

Quote:
Originally Posted by belovelife View Post
is there more potential energy in hydrogen peroxide HO+H=H2O
per volumetric ratio?
A simple way to compare the relative energies of various reactions is by comparing the molecular masses of their components. This gives us mass 2H +O -H2O = 0.0000407 AMU
H2O2 +2H -2H2O = 0.0000274 AMU
So the energy density of hydrogen fuel + hydrogen peroxide oxidizer (2H +H2O2 \to 2H2O) is about 67% that of hydrogen fuel + oxygen (2H +O \to H2O).

Hydrogen peroxide is also a monopropellant (H2O2 \to H2O + O) Since
H2O +O -H2O2 = 0.0000133 AMU
It’s has about 49% of the energy density of H + H2O2 bipropellant.

Energy density is usually the ration of available energy to mass of a fuel. It can be converted to an energy/volume ratio by using the combined average density of the fuel and oxidizer by the formula
d = \frac{m_1 +m_2}{\frac{m_1}{d_1}+\frac{m_2}{d_2}}
For 2H + O, this gives about 425 g/L, for 2H + H2O2, about 693. 2H + H2O2 monopropellant has density 1440 g/L. So, despite lower energy/mass ratios, the energy/volume ratios are:
2H +O -H2O = 100%
H2O2 +2H -2H2O = 111%
H2O +O -H2O2 = 110%

So in an application where compactness is important (eg: a road car) lower energy density fuels like hydrogen peroxide may be preferable to ones like hydrogen+oxygen. Hydrogen peroxide also is liquid at room temperature, so much simpler to use.


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