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What If ET Does Not Use Radio Waves



 
 
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  #1  
Old October 28th 08, 07:19 PM posted to sci.astro.seti
Bernard Isker
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Posts: 23
Default What If ET Does Not Use Radio Waves

A God given fact in Science is that nothing can travel faster than light.

What if the fact is wrong?

If a civilization has figured out how to travel faster than light then they
have also figured out how to communicate back to their home world at faster
than light speeds.

Maybe this is why we have not heard from them.

We have not figured out how to listen.


  #2  
Old October 29th 08, 06:43 AM posted to sci.astro.seti
Mike Williams
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Posts: 108
Default What If ET Does Not Use Radio Waves

Wasn't it Bernard Isker who wrote:
A God given fact in Science is that nothing can travel faster than light.

What if the fact is wrong?

If a civilization has figured out how to travel faster than light then they
have also figured out how to communicate back to their home world at faster
than light speeds.

Maybe this is why we have not heard from them.

We have not figured out how to listen.


As soon as you figure out how to communicate faster than light, let us
know the details and we'll start listening.

However, observations seem to show that the universe does conform to
Relativity Theory. That doesn't entirely rule out FTL communications,
but it does mean that any device that performs FTL communications can be
used to communicate through time and also breaks causality.

The smart money is on it being impossible for information to move faster
than light.

--
Mike Williams
Gentleman of Leisure
  #3  
Old October 29th 08, 07:56 AM posted to sci.astro.seti
Matt Giwer
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Posts: 523
Default What If ET Does Not Use Radio Waves

Bernard Isker wrote:
A God given fact in Science is that nothing can travel faster than light.
What if the fact is wrong?
If a civilization has figured out how to travel faster than light then they
have also figured out how to communicate back to their home world at faster
than light speeds.
Maybe this is why we have not heard from them.
We have not figured out how to listen.


The entire project is speculation only. So let us assume there is radio and
also something better, maybe many things better.

If they are attempting to say, we are here, then it is reasonable they would
use the oldest/simplest method possible. That appears to us to be radio. The
reason not to do that is if the use of radio is so short in their civilization
that they concentrate their efforts transmitting what they used the longest in
their past. Of course this would be speculation on their part.

For example if they used radio for 200 years and replaced it with something
they used for 2000 years their simplest assumption is their odds are ten times
greater using the replacement for radio.

My speculation on this is simpler. We are only a few decades away from being
able to observe planets around other stars. That will be less than 150 years
after radio. We will be able to see the lights at night on those planets. If
the issue is simply, you are not alone, then there is no reason to spend time
and money on what they expect other civilizations to be able to observe
"shortly" after they develop radio.

If they want to communicate there is still no use for radio as once we find
planets with lights at night it is certain we will be looking for modulated
laser transmissions from them on the assumption they have seen our lit
coastlines.

--
The lesson from this financial mess is the people on Wall Street are no more
qualified than you and I to run the country's finances.
-- The Iron Webmaser, 4058
http://www.giwersworld.org/environment/aehb.phtml a2
  #4  
Old October 29th 08, 01:28 PM posted to sci.astro.seti
Mike Williams
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Posts: 108
Default What If ET Does Not Use Radio Waves

Wasn't it Matt Giwer who wrote:
My speculation on this is simpler. We are only a few decades
away from being able to observe planets around other stars. That will
be less than 150 years after radio. We will be able to see the lights
at night on those planets.


Perhaps you've massively overestimated what it means to be able to
directly observe extrasolar planets. We are indeed only a few decades
away from being able to directly observe the light from extrasolar
planets, but the images we will get will show the target planets as
single pixels.

In order to be able to see artificial lights on a planet at a distance
of 10 light years, we'd need to build a telescope with a (synthetic)
aperture of something like 100 kilometres. Projects currently being
considered for launch in the next 20 years have synthetic apertures no
greater than 100 metres.

On the other hand, you might be speculating that some of the currently
proposed projects might be able to recognise the spectrum of light from
sodium or mercury vapour lamps. The problems there are that the little
green men might use lights that don't have a distinctive spectrum, our
proposed projects are mainly looking at the IR spectrum, and even if we
spotted the signature of sodium or mercury we'd be able to convince
ourselves that there was a possible natural explanation.

--
Mike Williams
Gentleman of Leisure
  #5  
Old October 29th 08, 05:51 PM posted to sci.astro.seti
Martha Adams
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Posts: 371
Default What If ET Does Not Use Radio Waves

"Mike Williams" wrote in message
...
Wasn't it Matt Giwer who wrote:
My speculation on this is simpler. We are only a few decades
away from being able to observe planets around other stars. That will
be less than 150 years after radio. We will be able to see the lights
at night on those planets.


Perhaps you've massively overestimated what it means to be able to
directly observe extrasolar planets. We are indeed only a few decades
away from being able to directly observe the light from extrasolar
planets, but the images we will get will show the target planets as
single pixels.

In order to be able to see artificial lights on a planet at a distance
of 10 light years, we'd need to build a telescope with a (synthetic)
aperture of something like 100 kilometres. Projects currently being
considered for launch in the next 20 years have synthetic apertures no
greater than 100 metres.

On the other hand, you might be speculating that some of the currently
proposed projects might be able to recognise the spectrum of light
from sodium or mercury vapour lamps. The problems there are that the
little green men might use lights that don't have a distinctive
spectrum, our proposed projects are mainly looking at the IR spectrum,
and even if we spotted the signature of sodium or mercury we'd be able
to convince ourselves that there was a possible natural explanation.

--
Mike Williams
Gentleman of Leisure


Yes, large synthetic apertures are the way to go and when we
have large-enough good ones, we can begin to see detail on
extra-solar planets. I think this turns on when we have
settlements off-Terra.

That's because the place to explore space from, is out in
space not here locally at the bottom of this Terran gravity
well. And when future generations in space have built their
basic human economic systems, independent of Terra, then they
can turn their eyes out to distant systems. Just think what
size synthetic instruments you could build in a Jupiter
trojan! Where it's *really* quiet and peaceful, we could
checkout solar systems in seconds where now it takes years;
observe close-up any blue gems spotted orbiting other stars.

When someone thinks maybe there's some mysterious Other
radiation where we can immediately discover the Aliens Out
There, I think he demonstrates his place at the extreme
bottom of any hierarchy of people who might know what they
are talking about.

Titeotwawki -- mha [sci.astro.seti 2008 Oct 29]


  #6  
Old October 31st 08, 01:20 AM posted to sci.astro.seti
Bernard Isker
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Posts: 23
Default What If ET Does Not Use Radio Waves

Another thing that has bothered me for a long time is the disincentive for
an advanced civilization to broadcast their presence. Notice that I say
advanced since a emerging civilization such as ours would not be "cloaking"
themselves until they became sufficiently advanced. The radio wave bubble of
an emerging civilization might last 200 years and then be replaced by
something better. This something better might them be replaced be something
even better after another X years and so on. Tuning to the differing methods
of communication would immediately indicate the sending civilizations level
of technology.

This advanced civilization would not know if other advanced civilizations
are "friendly" and to chance finding out could be disastrous.

On the other hand we see no evidence of a "Star Wars" occurring in our
Galaxy as far as we know. It may turn out that truly advanced civilizations
are all "peaceful". We better hope so since they know our level of
technology and if they are an aggressive advanced civilization we are in
trouble.


  #7  
Old November 2nd 08, 05:38 AM posted to sci.astro.seti
Matt Giwer
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Posts: 523
Default What If ET Does Not Use Radio Waves

Mike Williams wrote:
Wasn't it Matt Giwer who wrote:
My speculation on this is simpler. We are only a few decades
away from being able to observe planets around other stars. That will
be less than 150 years after radio. We will be able to see the lights
at night on those planets.


Perhaps you've massively overestimated what it means to be able to
directly observe extrasolar planets. We are indeed only a few decades
away from being able to directly observe the light from extrasolar
planets, but the images we will get will show the target planets as
single pixels.


In order to be able to see artificial lights on a planet at a distance
of 10 light years, we'd need to build a telescope with a (synthetic)
aperture of something like 100 kilometres. Projects currently being
considered for launch in the next 20 years have synthetic apertures no
greater than 100 metres.


You say the next 20 years. I was thinking about 50 years where the design
concepts are being developed today. So make it an entire century from now.
What's the rush?

I was thinking of putting telescopes in earth or solar orbit and using their
separation as the baseline.

On the other hand, you might be speculating that some of the currently
proposed projects might be able to recognise the spectrum of light from
sodium or mercury vapour lamps. The problems there are that the little
green men might use lights that don't have a distinctive spectrum, our
proposed projects are mainly looking at the IR spectrum, and even if we
spotted the signature of sodium or mercury we'd be able to convince
ourselves that there was a possible natural explanation.


I am simply thinking that of the dark side isn't dark it is massive vulcanism
or artificial. Have you ever seen the NASA composite image of the earth at
night? It won't take much resolution to separate refraction of a dense
atmosphere from lights on the ground. The world's coasts are outlined in
lights. We have no natural affinity to the sea shore. Of course every cultural
will not do this but on the assumption we are average which has worked out
quite well in astronomy there should be enough with lights along the shore to
keep us busy for a long time.

--
McCain's choice of Palin disqualifies him
for public office.
-- The Iron Webmaster, 4061
http://www.giwersworld.org/israel/bombings.phtml a5
  #8  
Old November 2nd 08, 05:58 AM posted to sci.astro.seti
Matt Giwer
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Posts: 523
Default What If ET Does Not Use Radio Waves

Bernard Isker wrote:
Another thing that has bothered me for a long time is the disincentive for
an advanced civilization to broadcast their presence. Notice that I say
advanced since a emerging civilization such as ours would not be "cloaking"
themselves until they became sufficiently advanced.


By the time we thought of the risks of advertising our presence we had our
cities lit up at night. Thus if the method of detection is telescopes then by
the time you think not to advertise you have been doing it for decades. And
there is no way to take it back. Blackouts are closing the barn door after the
horse is gone.
....
On the other hand we see no evidence of a "Star Wars" occurring in our
Galaxy as far as we know. It may turn out that truly advanced civilizations
are all "peaceful". We better hope so since they know our level of
technology and if they are an aggressive advanced civilization we are in
trouble.


One has to ask why anyone would be aggressive unless the folks out there are
thinking about limiting population growth. What is the point of taking over an
inhabited planet when there are more uninhabited planets? With no apologies to
Independence Day, why the hassle with Earth when our moon, Mars, other moons,
Mercury and the asteroid belt are all for the taking without any exotic
technology needed for Venus?

I would guess the best place to look for resources is a star with an
accretion disk but where the planets have not yet formed. That would be a huge
and ultra-dense asteroid belt.

--
God is a single parent who sent his son to earth on a suicide mission.
-- The Iron Webmaster, 4065
http://www.giwersworld.org/palestine/answers.phtml a9
  #9  
Old November 2nd 08, 07:03 AM posted to sci.astro.seti
Mike Williams
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Posts: 108
Default What If ET Does Not Use Radio Waves

Wasn't it Matt Giwer who wrote:
In order to be able to see artificial lights on a planet at a
distance of 10 light years, we'd need to build a telescope with a
(synthetic) aperture of something like 100 kilometres. Projects
currently being considered for launch in the next 20 years have
synthetic apertures no greater than 100 metres.


You say the next 20 years. I was thinking about 50 years where
the design concepts are being developed today. So make it an entire
century from now. What's the rush?

I was thinking of putting telescopes in earth or solar orbit and
using their separation as the baseline.


I don't think that there are any serious designs being worked on for
such large separations yet. You can't just take designs that work for
100 metres separation and expand them to work for thousands of
kilometres. One significant problem is that you have to fly the mirrors
in a formation that's accurate to the precision of less than a
wavelength of the light that you're trying to capture, but the
measurement and adjustment signals are subject to light speed delays.

As well as the problem of raw resolution, there's also the problem that
the planet is rather close to a sun that's billions of times brighter.

I guess those problems may be resolvable, but I don't see it happening
until an awful long time we've already determined whether there's a
technological civilization on the target planet by observing the
spectrum of the pollution in their atmosphere.

--
Mike Williams
Gentleman of Leisure
  #10  
Old November 3rd 08, 04:58 AM posted to sci.astro.seti
Matt Giwer
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Posts: 523
Default What If ET Does Not Use Radio Waves

Mike Williams wrote:
Wasn't it Matt Giwer who wrote:
In order to be able to see artificial lights on a planet at a
distance of 10 light years, we'd need to build a telescope with a
(synthetic) aperture of something like 100 kilometres. Projects
currently being considered for launch in the next 20 years have
synthetic apertures no greater than 100 metres.

You say the next 20 years. I was thinking about 50 years where
the design concepts are being developed today. So make it an entire
century from now. What's the rush?
I was thinking of putting telescopes in earth or solar orbit and
using their separation as the baseline.


I don't think that there are any serious designs being worked on for
such large separations yet. You can't just take designs that work for
100 metres separation and expand them to work for thousands of
kilometres.


I did not invent this idea. I have about them in the conceptual design phase.

One significant problem is that you have to fly the mirrors
in a formation that's accurate to the precision of less than a
wavelength of the light that you're trying to capture, but the
measurement and adjustment signals are subject to light speed delays.



As you know what you has to be corrected it is all in the engineering.
Nothing is going to move them even a fraction of a wavelength once in orbit.
There is some experiment in earth orbit now in what is described as a
"formation" where knowing the precise separation distances are important.
Probably looking for gravity waves. I forget just what they are doing.

As well as the problem of raw resolution, there's also the problem that
the planet is rather close to a sun that's billions of times brighter.


For us it is 92,000,000 miles away from a star with a 400,000 mile radius.
Physically blocking the star's light appears doable. We do it right now on
that satellite observing the solar wind.

I guess those problems may be resolvable, but I don't see it happening
until an awful long time we've already determined whether there's a
technological civilization on the target planet by observing the
spectrum of the pollution in their atmosphere.


Thus spake Al Gore. We are at most a century away from being all electric
powered by fission or fusion. There goes the quantity of pollution would could
be considered a unique sign of an industrial society.

--
Being against any particular war does not require being against all wars.
Professional pacifists leech off of every mistaken war making it nearly
impossible to end even the most disastrous war.
-- The Iron Webmaster, 4060
http://www.giwersworld.org/holo/nizgas3.html a4
 




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