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UFO/ET… How sceptic are you ?
Posted: 09 November 2010 11:59 PM   [ Ignore ]   [ # 61 ]
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OK, but at the speed of light it requires much more power to accelerate at the same rate as at lower speeds.
Similar to hull speed of a boat. Eventually no amount of power will be able to make it go faster.

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Posted: 10 November 2010 12:10 AM   [ Ignore ]   [ # 62 ]
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With conventional physics this is true.  The speed of light does seem to be the cosmic speed limit.

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Posted: 10 November 2010 12:29 AM   [ Ignore ]   [ # 63 ]
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VenomFangX - 10 November 2010 12:10 AM

With conventional physics this is true.  The speed of light does seem to be the cosmic speed limit.

My question was if the increase in power demand vs a steady increase in speed is an exponential function.

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Posted: 10 November 2010 12:37 AM   [ Ignore ]   [ # 64 ]
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By increasing the speed you are increasing the kinetic energy.  This as you know is 0.5MV2.  This means as you double the speed you need four times the amount of energy to get there.  For mass to reach the speed of light would take infinite energy.

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Posted: 10 November 2010 10:51 AM   [ Ignore ]   [ # 65 ]
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Intelligent life evolving upon another planet and somehow developing interstellar travel and visiting our planet, with the government successfully covering it up is not impossible, but it is highly unlikely.

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Posted: 10 November 2010 07:38 PM   [ Ignore ]   [ # 66 ]
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I don’t know if it was covered earlier, but as one goes faster, one develops more mass.  As you approach the speed of light your mass approaches infinity.  This means to accelerate, one must apply greater energy or force, the amount of that also approaching infinity. 

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Posted: 11 November 2010 01:06 AM   [ Ignore ]   [ # 67 ]
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This is true: there is a precise mathematical formula which is correct about velocity and mass increase.  The same issue occurs with spatial dimensions and time.

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Posted: 14 November 2010 11:10 AM   [ Ignore ]   [ # 68 ]
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I do not think it is possible for extraterrestrial life forms to travel to our planet.  I hold that there is a slim possibility that intelligent extraterrestrials could send inorganic unmanned (un-aliened?) probes to planets including ours.  These probes could be built to last a long time.  But the probability that the UFO sightings are sightings of extraterrestrial technology is rather low.  There is a rather high possibility of hoaxes.  Also, often top secret experimental human-built aircraft are often considered UFO’s by the general public.  For example, the stealth bomber was being flown around for about 8 years before the general public was informed of its existence.  Remember that news story about that balloon that took off that was rumored to be carrying the builder’s son?  If you saw it, you would notice that it was silver, round and flat on top.  Maybe his original intent was to create a UFO hoax.

One guy I knew, who was once a member of the Special Forces, told me that there is actually stealth helicopter made by Bell aircraft that is a triangle with 3 rotors and sightings of it make up a lot of UFO sightings.  Apparently in a few years the general public will be informed of its existence.

I once saw an object at night in the sky moving with what seemed like amazing speed and seemed to reverse direction just like UFO’s are shown to do on those TV shows.  When I got a better angle on it, it was clear that the object was a lot closer and a lot smaller than it first appeared.  It was a gull flying above a field that had lights on around it for a nighttime soccer game.  The lights from the field lit up the bottom of the bird, which was flying in circles.  Whenever it reached a part of its circle in which it was flying either toward or away from me, it appeared to be stopping and changing direction.  The point of that is that the human visual system is not 100% reliable, and optical illusions are so common that they can account for many UFO sightings.

It is so much more likely that a UFO sighting is either a hoax, an optical illusion or a misidentified piece of human technology than a piece of extraterrestrial technology, that it does not make sense to conclude that any of them are of extra-terrestrial origin.

[ Edited: 14 November 2010 05:29 PM by Tradition Of Progress ]
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Posted: 20 November 2010 01:05 PM   [ Ignore ]   [ # 69 ]
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Well let me say as a Sci Fi fan I do hope they exist, it would definitely make the world more interesting.

If they happen to have a civilization a billion or more years older then ours then their technology would have to be so great as to look magical to us (or so I’m told) and if so who knows what kind of technology they might have. Could they have technology to bypass the billions of miles involved? During the Civil War who would have thought in the not so distant future we would have Jets that could go many times the speed of sound and have the computers we have today? If you would have asked them then I would bet they would think your nuts. We have absolutely no way of knowing unless we actually see one up close.

By the way has anyone seen the “Above Top Secret” web site? WOW, some crazy stuff.

[ Edited: 20 November 2010 03:39 PM by Ibby14 ]
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Posted: 20 November 2010 06:02 PM   [ Ignore ]   [ # 70 ]
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Ibby14 - 20 November 2010 01:05 PM

Well let me say as a Sci Fi fan I do hope they exist, it would definitely make the world more interesting.

I too am a Sci Fi Fan, and agree that they would make the world or universe more interesting.  I would like them to exist too.  So much so, that if I had too much time and money on my hands then maybe I would create hoaxes.  A lot of people want them to exist, which means that the chance of creating hoaxes or mistaking birds flying over a field for something else is rather high.

If there were a far more advanced race of beings that can travel to our planet, then would they really want to meet us?  If I were one of them, I would not want humans traveling to my planet and leaving soda cans, juice boxes, cigarette butts, and gum wads all over the ground.  Before humans should even be given technology to allow them to explore other worlds, they should learn more about themselves.

There are rather interesting life forms already on our own planet, some that have been discovered more recently that others, for example bioluminescent cephalopods and others living in the deep ocean.  We already have another “world” to learn about on own own planet.  There is still more to learn and understand about our own planet and our own species.

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Posted: 20 November 2010 06:35 PM   [ Ignore ]   [ # 71 ]
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Tradition Of Progress - 20 November 2010 06:02 PM
Ibby14 - 20 November 2010 01:05 PM

Well let me say as a Sci Fi fan I do hope they exist, it would definitely make the world more interesting.

I too am a Sci Fi Fan, and agree that they would make the world or universe more interesting.  I would like them to exist too.  So much so, that if I had too much time and money on my hands then maybe I would create hoaxes.  A lot of people want them to exist, which means that the chance of creating hoaxes or mistaking birds flying over a field for something else is rather high.

If there were a far more advanced race of beings that can travel to our planet, then would they really want to meet us?  If I were one of them, I would not want humans traveling to my planet and leaving soda cans, juice boxes, cigarette butts, and gum wads all over the ground.  Before humans should even be given technology to allow them to explore other worlds, they should learn more about themselves.

There are rather interesting life forms already on our own planet, some that have been discovered more recently that others, for example bioluminescent cephalopods and others living in the deep ocean.  We already have another “world” to learn about on own own planet.  There is still more to learn and understand about our own planet and our own species.

Absolutely.

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Posted: 20 November 2010 07:15 PM   [ Ignore ]   [ # 72 ]
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I’ve mentioned it before, but in case you missed,  there is a salamander The “silvery”, in which the eggs of female have a double (mirror) strand of her chromosomes. However it has learned to “mate” without accepting the sperm of the male. Thus all offspring are female and identical clones of the mother. They live in a few ponds in Illinois, US. and as there are but some 60 , they are very protected. A true genetic mutation that is doomed to failure.
http://news.medill.northwestern.edu/chicago/news.aspx?id=90277
http://www.pingleton.com/LifeList/platineum.htm

[ Edited: 20 November 2010 07:31 PM by Write4U ]
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Posted: 21 November 2010 03:57 AM   [ Ignore ]   [ # 73 ]
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Write4U - 10 November 2010 12:29 AM
VenomFangX - 10 November 2010 12:10 AM

With conventional physics this is true.  The speed of light does seem to be the cosmic speed limit.

My question was if the increase in power demand vs a steady increase in speed is an exponential function.

The answer is yes and no.  The no is because is a steady increase in velocity from your measurement and perspective as the accelerator never requires more energy then it did last time.  A “constant burn” always has a constant effect from your current reference frame [were ignoring the fact that you are accelerating less mass as the burn goes to make a point].  It is one of the profound aspects of relativity that is surprisingly often neglected in forum expertise.  You can understand the change of energy required by the disagreement about clocks and the consequences that has for “constant burn”.  You never disagree with yourself about your own clock assuming your the one accelerating =) From other peoples perspective though your constant increase in velocity per a unit time will eventually take an exponential increasing amount of energy(instantaneousness) and then become worse…  Because your “constant expenditure of energy” is only constant from your perspective.  It would appear to deviate from outside your perspective.

You can think about http://en.wikipedia.org/wiki/Time_dilation , and then pretend your in a ship that is doing something to turn stored energy into velocity that is repeated every 1 second.  The people observing you from planets see your energy expenditure drop off per a second of their time and thus you appear to not accelerate as much in any given second of their time.  To keep that acceleration constant from their perspective you will need to adjust for their perception of your time dilation in your burn.  But, to keep it constant relative to your own clock: do nothing. 

One of the other profound aspects of “speed of light” as some constant speed limit is in absence of external references you are never any closer to the “speed of light” though people often act as if you are.  And, if a new external reference comes into play that is doing your velocity you both proceed as if you were sitting at rest for all the universe is concerned for describing the rules of physics.  At some level, I suppose this means that our sense of the rules of physics is probably intuitively off or perhaps that special relativity is the correction to our natural intuitive way to describe the universe, but in that act is perceived as bizarre.

Though back to the top of the thread, there are some novel out of the box ways to get a ship to another planet in low finite time if you want to throw very large finite time at preparation.  For example, one criticism of a low finite time ship getting to another planet carrying a person is that you can’t carry the fuel and resources for life support and accelerate it.  What if you don’t?  What if you blast off from earth every year an unmanned seeder ship that drops fuel, food, and resources on a preselected spot such that when another ship blast off from earth in some distant future it will hit all those fuel drops directly on its flight path.  The math is surely nasty, and the engineering requirements immense.  But you could do it…

[ Edited: 21 November 2010 04:04 AM by qutsemnie ]
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Posted: 11 December 2010 12:10 AM   [ Ignore ]   [ # 74 ]
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Why does everyone automatically assume that an interstellar starship would have to carry fuel?

All the world’s ocean trade for thousands of years travelled in vessels that carried no fuel for propulsion. They used an ancient technology called “sailing”, whereby they employed sheets of fabric to intercept a small part of a naturally occuring flow of energy and convert the intercepted energy into forward motion - thermodynamically a surprisingly efficient process.

Allright, solar sails provide only a very slow, but sustained, accelleration, and lose efficiency as they travel away from the sun; but some future development along these lines might yet result in a viable (perhaps multigenerational) starship.

Then there’s the Bussard ramjet, that uses an electromagnetic field to scoop up interstellar hydrogen and uses the hydrogen to power a fusion reactor. We’re a long way from building even a pilot model, but in a few centuries - who knows?

Certainly, there has to be a better way than simply squirting reaction mass out of the rear of your ship, which means that -what is it? 85%? - of the mass of the ship has to consist of fuel and fuel-handling systems. That has to be the most inefficient way of getting off the ground that it’s possible to imagine.

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Posted: 21 December 2011 04:38 PM   [ Ignore ]   [ # 75 ]
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Occam - 04 August 2010 04:42 PM

I would have preferred that you give a more nuanced list of choices.  On a scale of zero to ten, with the last choice being zero and the middle choice being five I would have chosen one.  However, I was forced to choose the third choice. 

While I feel it’s quite likely that there are a great number other worlds with conditions similar to ours which have developed life, and at least some of that life has developed intelligence.  The main problem is the huge distance between stars.  As such, I think it’s highly unlikely that any of us, the intelligent beings on any planet, will be able to traverse those distances.

Occam

Even though I would have voted a 4, I totally agree with Occam, since I had to pick the middle choice while not being much of a believer. I do not believe in the ET origins of crop circles, in abductions, in Nazca or ancient astronauts or anything New Age such as Von Daniken’s claims. I do not even believe that Area 51 is an alien landing site or that an earthly government, US or else, has recovered any bodies or craft. I do not believe these claims not because they seem outlandish or far-fetched, but beause any document I have consulted on the topic came up to be nothing else than opinion, some interesting, some not. No picture or video I have seen has ever convinced me. Some (a very tiny minority) are indeed puzzling, but NOTHING links these strange sightings to alien visitations, unless someone uses false assumptions and flawed axioms.

The only element that poises me are the military reports of interaction with unidentifed objects in the skies. These occurrences are not only made of testimonies, they include written repports and radar readings in both the interceptor jets sent towards these objects and ground radar stations. These objects were chased by our most modern aircraft of the time and always escaped them with much ease, and seemed to react to aircraft presence. Such sightings were made by seasoned military servicemen, including senior officers and astronauts, who, under oath, stuck to their versions that it was no natural phenomena.

I am more than ready to believe it can be anything but extra-terrestrial vehicles… but what is it then? Since “believer” litterature take the ET hypothesis for granted and “skeptic” publishings not only discard but seldom analyze these very specific events, it is quite hard to have a clear opinion backed by facts on either side.

Does anyone have a clue of what these objects might be?

Thanks.

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