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estebanana

 

Posts: 7545
Joined: Oct. 16 2009
 

RE: Richard and other thinkers (in reply to Ruphus

How's your painting going?

_____________________________

https://www.stephenfaulkguitars.com
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 7 2014 7:09:20
 
Ricardo

Posts: 11363
Joined: Dec. 14 2004
From: Washington DC

RE: Richard and other thinkers (in reply to tele

quote:

ORIGINAL: tele

People who say complicated things like time travel is impossible are impossible. I think we are very primitive still in terms of technology.



Probably. But the current obstacles are not really understood by the general public it seems. Most feel like "we go faster than sound and everyone thought that was impossible so why not light?"...and of course they are thinking big fat space ships. Now there might be clever work arounds in theory but first we must come to grips with WHY things might need to be "worked around". Faster than light and back in time are such concepts. Work arounds for light speed will involve "bending" of space time....and perhaps the time travel thing might tie in to teleportation idea that requires using entangled particles. But it is still fringe and the concept of difficulty, not fringe work arounds, I think needs to be well understood by everyone first, in hopes a light bulb might go off in some genius mind.

_____________________________

CD's and transcriptions available here:
www.ricardomarlow.com
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 7 2014 11:59:36
 
gmburns

Posts: 157
Joined: Nov. 20 2012
 

RE: Richard and other thinkers (in reply to estebanana

quote:

ORIGINAL: estebanana

How's your painting going?


Depends. Don't want to hijack the thread, but I'm finishing an abstract cityscape line which has become pretty popular. This line could be a key to my first gallery exhibit, but we'll see. However, no sales.

I'm working on developing my watercolor skills, too. I really like the medium and I think it suits my style pretty well, especially with the use of white paper, but that's still coming along.

The exhibit for the fundraiser sold one painting. It's brutal here. Or maybe I'm just not that good. I guess time will tell. The good news is that the spot on the wall where I've been banging my head is pretty well indented and my head is only partially sore. I must be doing something right.

I really need a mentor.


City V - Love Towers
Oil on Canvas (2014)
50 x 100 cm


City IV - Spanish Sunset
Oil on Canvas (2014)
50 x 100 cm


Colonia del Sacramento
Watercolor on Paper (2014)
21 x 29 cm

Images are resized automatically to a maximum width of 800px

_____________________________

Greg Mason Burns - Artist
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 7 2014 12:32:48
 
gmburns

Posts: 157
Joined: Nov. 20 2012
 

RE: Richard and other thinkers (in reply to Ricardo

quote:

ORIGINAL: Ricardo

quote:

ORIGINAL: tele

People who say complicated things like time travel is impossible are impossible. I think we are very primitive still in terms of technology.



Probably. But the current obstacles are not really understood by the general public it seems. Most feel like "we go faster than sound and everyone thought that was impossible so why not light?"...and of course they are thinking big fat space ships. Now there might be clever work arounds in theory but first we must come to grips with WHY things might need to be "worked around". Faster than light and back in time are such concepts. Work arounds for light speed will involve "bending" of space time....and perhaps the time travel thing might tie in to teleportation idea that requires using entangled particles. But it is still fringe and the concept of difficulty, not fringe work arounds, I think needs to be well understood by everyone first, in hopes a light bulb might go off in some genius mind.


I think part of it, too, is that the result needs to have a practical application in today's world. By today's world I mean that scientists need to be working on something that they can reasonably see how the outcome can be valued, whether that be right now or 250 years in the future. The point is that they are close enough to understanding that they can see a benefit.

Right now there are too many other questions that are more important, and therefore this study of time travel, for example, is a mere result of other research designed to "discover" other "goals." I think very few people are actually studying time travel as a specific end.

_____________________________

Greg Mason Burns - Artist
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 7 2014 12:40:05
 
Ruphus

Posts: 3753
Joined: Nov. 18 2010
 

RE: Richard and other thinkers (in reply to gmburns

quote:

ORIGINAL: gmburns

Right now there are too many other questions that are more important, ...


Indeed, in both views, regarding issues and common sense´s evaluation of them.

For instance Ricardo´s pointing to general public´s understanding instantly reminded me of the problem of extinction.

It seems pretty clear that people do not fathom what extinction means. And following up has revealed several times to me that folks actually expect extinct species to re-occure within some historically manageable time frame.

That must explain for a part how come people resume their ways as if nothing had changed over past decades.

There is an urgent need for educating the people on what extinction of higher developed species actually means and how it will effect eco systems and men.

For secondly, people seem to think one could survive just like before as long as there be an iPad and maybe some plants as hydroculture or so. Or worse even situated in the rubbish of a space ship.

Just look at the volunteers who have already registered for travel to Mars.
These poor people have not even enough imagination to foresee how the initially romantic Kubrick-Space-Odysee will be turning into desperate regrets and psychosis.

How should such shallow thinking on the other hand allow to yet realize what a vanishing of flora and fauna will be meaning to the unnatural and exhausting life of future people?
-

Indeed, there are much more important matters to explore on and to be educated about than TT.


-Even though from an era of persihing and escalation to come, TT could easily remain the one and only option for enabling a living in a naturally adequate future.
IOW, hoping for an overcoming of a destroyed evolution is as foolish as it gets.

Ruphus
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 7 2014 14:02:44
 
gmburns

Posts: 157
Joined: Nov. 20 2012
 

RE: Richard and other thinkers (in reply to Ruphus

quote:

ORIGINAL: Ruphus

quote:

ORIGINAL: gmburns

Right now there are too many other questions that are more important, ...


Indeed, in both views, regarding issues and common sense´s evaluation of them.

For instance Ricardo´s pointing to general public´s understanding instantly reminded me of the problem of extinction.

It seems pretty clear that people do not fathom what extinction means. And following up has revealed several times to me that folks actually expect extinct species to re-occure within some historically manageable time frame.

That must explain for a part how come people resume their ways as if nothing had changed over past decades.

There is an urgent need for educating the people on what extinction of higher developed species actually means and how it will effect eco systems and men.

For secondly, people seem to think one could survive just like before as long as there be an iPad and maybe some plants as hydroculture or so. Or worse even situated in the rubbish of a space ship.

Just look at the volunteers who have already registered for travel to Mars.
These poor people have not even enough imagination to foresee how the initially romantic Kubrick-Space-Odysee will be turning into desperate regrets and psychosis.

How should such shallow thinking on the other hand allow to yet realize what a vanishing of flora and fauna will be meaning to the unnatural and exhausting life of future people?
-

Indeed, there are much more important matters to explore on and to be educated about than TT.


-Even though from an era of persihing and escalation to come, TT could easily remain the one and only option for enabling a living in a naturally adequate future.
IOW, hoping for an overcoming of a destroyed evolution is as foolish as it gets.

Ruphus



One word: bees.

_____________________________

Greg Mason Burns - Artist
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 7 2014 14:16:15
 
BarkellWH

Posts: 2893
Joined: Jul. 12 2009
From: Washington, DC

RE: Richard and other thinkers (in reply to Ricardo

Actually, given our current knowledge and understanding of the laws of physics governing the universe, it does not appear possible to travel back in time. There are interesting ideas such as hypothetical wormholes and parallel universes that might provide a theoretical basis for time travel to the past, but they are strictly hypothetical at this point. I think that most physicists would say that nothing in our current understanding of physics and cosmology would allow for even theoretical time travel to the past.

There is a theoretical basis for time travel to the future, however, and it owes its existence to Einstein's Theory of Special Relativity governing space-time. Under Special Relativity, time slows down the faster one increases one's speed. This is an experimentally verified prediction of Special Relativity. As Brian Greene, in "The Fabric of the Cosmos" explains it, if one could build a vehicle that would reach 99.999996 percent of the speed of light and one headed off at full throttle into deep space for one day, ten days, or 27 years according to your ship's clock, then abruptly turned around and headed back to earth at full throttle, on one's return 1,000, or 10,000, or 10 million years of earth time will have elapsed. One will have returned to the future on earth, as earth-time will have elapsed at its much faster, normal rate than the dilated time that had slowed in one's speeding ship.

To sum up my understanding of the current state of play, the laws of physics prevent us from time travel back to the past. But it is technology (we cannot build a vehicle to reach such speeds) that prevents us from traveling to the future. Nevertheless, the laws of physics (Special Relativity) provide a theoretical basis for time travel to the future.

Cheers,

Bill

_____________________________

And the end of the fight is a tombstone white,
With the name of the late deceased,
And the epitaph drear, "A fool lies here,
Who tried to hustle the East."

--Rudyard Kipling
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 7 2014 15:18:02
 
Ricardo

Posts: 11363
Joined: Dec. 14 2004
From: Washington DC

RE: Richard and other thinkers (in reply to BarkellWH

Almost theoretical idea for backwards time travel. And seriously studied for a long time before Tachyon Condensation was discovered.

http://en.wikipedia.org/wiki/Tachyonic_antitelephone

Forward time travel I thought was even beyond the theoretical in the sense they have achieved forward time travel already, using atomic clocks and high altitude aircraft.

Further, the "Orion" spacecraft has been within our technological ability to construct since the late 70's and could achieve speeds allowing for relativistic time dilation effects. It was abandoned as a project after treaty forbidding nuke detonations in space.

_____________________________

CD's and transcriptions available here:
www.ricardomarlow.com
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 7 2014 17:02:53
 
Richard Jernigan

Posts: 2681
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: Richard and other thinkers (in reply to BarkellWH

quote:

ORIGINAL: BarkellWH

There is a theoretical basis for time travel to the future, however, and it owes its existence to Einstein's Theory of Special Relativity governing space-time. Under Special Relativity, time slows down the faster one increases one's speed. This is an experimentally verified prediction of Special Relativity. As Brian Greene, in "The Fabric of the Cosmos" explains it, if one could build a vehicle that would reach 99.999996 percent of the speed of light and one headed off at full throttle into deep space for one day, ten days, or 27 years according to your ship's clock, then abruptly turned around and headed back to earth at full throttle, on one's return 1,000, or 10,000, or 10 million years of earth time will have elapsed. One will have returned to the future on earth, as earth-time will have elapsed at its much faster, normal rate than the dilated time that had slowed in one's speeding ship.

Cheers,

Bill


There is a quibble with this story, which has echoed through the popular press for decades, probably for a century.

Special Relativity deals only with inertial coordinate systems, traveling at constant velocity relative to one another. If the rocket passenger were truly in an inertial coordinate system, he would be entitled to consider himself at rest, and to apply the Lorentz transformation to the Earth clocks. This would result in paradox. Upon his return, the rocket passenger would see the Earth as retarded, the earthlings would see the rocket passenger as younger than his earthbound twin.

This is the "Twin Paradox" which has circulated ever since I first read about relativity as a young teenager.

But to apply Special Relativity, you must be in an inertial coordinate system. If you stay in an inertial coordinate system, you can't go home again. You must travel with constant velocity relative to your point of departure, on a straight line through Euclidean space.

Not only can you not go home again, gravity makes space non-Euclidean, as shown by gravitational lensing of light from distant galaxies.

The resolution is that Special Relativity doesn't apply to the example of the round-trip rocketeer. In order to come home again, he must be subjected to acceleration, which brings General Relativity into play.

The time dilation really does occur. Cosmic ray particles descending rapidly through the atmosphere have a longer half life than the same kind of particle traveling at slower speeds in the laboratory.

I knew well the men who measured time dilation with an atomic clock carried aboard airliners in a round-the-world trip. Time dilation of the clock in an orbiting satellite was measured around the same time by a group I was acquainted with, but not as well as with the airliner guys.

Accurate compensation for the time dilation effect is crucial to the operation of the GPS receiver in your iPad or on the dashboard of your car, due to the appreciable velocity of the orbiting satellites whose signals provide the information needed to calculate your position and time in standard earth coordinates.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 8 2014 0:19:09
 
BarkellWH

Posts: 2893
Joined: Jul. 12 2009
From: Washington, DC

RE: Richard and other thinkers (in reply to Richard Jernigan

quote:

There is a quibble with this story, which has echoed through the popular press for decades, probably for a century....Upon his return, the rocket passenger would see the Earth as retarded, the earthlings would see the rocket passenger as younger than his earthbound twin. This is the "Twin Paradox" which has circulated ever since I first read about relativity as a young teenager.

But to apply Special Relativity, you must be in an inertial coordinate system. If you stay in an inertial coordinate system, you can't go home again. You must travel with constant velocity relative to your point of departure, on a straight line through Euclidean space.

Not only can you not go home again, gravity makes space non-Euclidean, as shown by gravitational lensing of light from distant galaxies. The resolution is that Special Relativity doesn't apply to the example of the round-trip rocketeer. In order to come home again, he must be subjected to acceleration, which brings General Relativity into play.

The time dilation really does occur.


I first read about special and general relativity as a teenager as well. Still in high school, I was in Arizona State University's bookstore one day and bought a copy of George Gamow's primer, "One, Two, Three, Infinity." It was my introduction to relativity and the cosmos and really inspired a continuing layman's interest in the topic. I no longer have it (it was more than 50 years ago), but Brian Greene's, "The Fabric of the Cosmos" is very good on all the latest thinking on cosmology. Both mention the theoretical possibility of traveling close to the speed of light into deep space, decelerating to turn around and then accelerating to near speed of light for a return to earth. Upon return to Earth, the rocketeer would have aged at a slower rate due to dilation of time (special relativity), while many more Earth years would have passed on Earth. Thus, from the rocketeer's point of view, his return to the Earth of the future.

Regarding your quotes I have cited above, assuming the example I used of the round-trip:

I don't know what you mean by the "rocket passenger would see the Earth as retarded." What do you mean by "retarded"? Your statement concerning the "Twin Paradox": "The earthlings would see the rocket passenger as younger than his earthbound twin," was mentioned by Gamow more than 50 years ago and suggests that, as Gamow and Greene, and others, have pointed out, from the rocketeer's point of view, he would have returned to an Earth that had aged much more than he, i.e., a return to an Earth of the future, from his perspective. Time dilation indeed has been demonstrated with atomic clocks and aircraft flying long distance.

The gravitational "lensing" of the light from distant galaxies indeed confirmed general relativity's theory that mass curves and bends space (the gravitational effect). If I read you correctly, you appear to consider special relativity and general relativity to be mutually exclusive, e.g., your statement, "The resolution is that Special Relativity doesn't apply to the example of the round-trip rocketeer. In order to come home again, he must be subjected to acceleration, which brings General Relativity into play." I don't see special and general relativity as mutually exclusive. Both are theories that explain certain phenomena in the universe occurring simultaneously. Theoretically, I don't see why special relativity couldn't explain "time dilation" on a trip near the speed of light, and general relativity be used to explain why the rocketeer indeed can return to earth hurtling through non-Euclidean space. Greene and other theoretical physicists and cosmologists seem to think it theoretically possible.

Cheers,

Bill

_____________________________

And the end of the fight is a tombstone white,
With the name of the late deceased,
And the epitaph drear, "A fool lies here,
Who tried to hustle the East."

--Rudyard Kipling
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 8 2014 12:02:35
 
Ruphus

Posts: 3753
Joined: Nov. 18 2010
 

RE: Richard and other thinkers (in reply to BarkellWH

quote:

ORIGINAL: BarkellWH


The gravitational "lensing" of the light from distant galaxies indeed confirmed general relativity's theory that mass curves and bends space (the gravitational effect).


I believe such to be currently revisited under new factor of black material.
Black material and black energy seem to be shaking through theorems of up to date.

Ruphus
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 8 2014 15:25:13
 
Ricardo

Posts: 11363
Joined: Dec. 14 2004
From: Washington DC

RE: Richard and other thinkers (in reply to BarkellWH

quote:

If I read you correctly, you appear to consider special relativity and general relativity to be mutually exclusive,


Don't mean to cut in but I think, as a layman, that the time dilation deal is more the result of the GENERAL theory of relativity...you see Einstein had that cool special relativity idea about light speed yada yada... but it meant there was a problem with TIME. In other words, in special relativity idea, if the sun vanished, according Newton gravity, Earth would instantly fly straight off in space. A violation of Special Relativity occurs in that scenario, no info can go faster than light....so Einstein had to conceive of SPACE-TIME as a single fabric to account for this paradox. Then it takes 8 minutes of time due to the ripple of space time to reach earth after the Sun vanishes, hence no violation of speed of C. So you can't really take special Relativity by it'self when you talk of space travel and TIME dilation effect and such. That is all a result of GENERAL theory of Relativity, the one that really matters with GPS and such as well.

hope that helps a little.

Ruphus, black material and energy and such is not really shaking up General Relativity except with Fringe scientists entertaining long abandoned concepts such as MOND (modified newtonian dynamics). The vast majority still look for MATTER, however weakly interacting as culprit of current observational oddities. Einstein still never been experimentally proven WRONG. That is what counts.

_____________________________

CD's and transcriptions available here:
www.ricardomarlow.com
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 8 2014 22:59:22
 
Richard Jernigan

Posts: 2681
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: Richard and other thinkers (in reply to BarkellWH

In general, the word "relativity" in physics arose to point out that there was no preferred coordinate system for the laws of physics.

Why did people ever think there would be? Maxwell's highly successful formulation of electrodynamics implied that there was a preferred coordinate system. Electromagnetic waves were seen as propagating through a stationary medium, the "luminiferous ether". So if an observer were moving with respect to this medium, the velocity of light would be affected by the observer's motion, just as we strike the waves more often as we speed up our boat, or sound gets to us quicker if it's traveling downwind.

The existence of a preferred coordinate system was an absolutely unavoidable mathematical consequence of combining Maxwell's equations and Newtonian dynamics, regardless of whether it was materially manifested.

Various experiments were devised to detect the "luminiferous ether", or in the more modern view, the preferred coordinate system, where the velocity of light was that predicted by Maxwell's equations. All failed in an unexpected way. No variation in the observed speed of light was detected. Michelson and Morley's experiments in 1887 were particularly well designed, precise and well documented. The observed velocity of light was the same throughout the year, as the earth moved in its orbit at high velocity through the assumed preferred system. Michelson and Morley put the fox among the chickens.

Einstein's 1905 paper "On the Electrodynamics of Moving Bodies" explored the implications of the absence of a stationary luminiferous ether, or preferred coordinate system. The results are called the theory of Special Relativity. He derived the Lorentz transformation from the following postulates: 1) The laws of physics are the same in all inertial coordinate systems, 2) the speed of light is the same for all observers.

Postulate 1) has considerable tacit content. An inertial coordinate system is one in which space is Euclidean, and which undergoes no acceleration. Such coordinate systems are mathematical abstractions which do not exist in nature. Space is warped by the presence of mass and energy, and the forces of nature, in particuar gravity exist throughout the universe, subjecting every observer and his coordinate system to acceleration.

Exploring the abstraction a little further, in effect, if A and B are two inertial coordinate systems, then A sees B as moving in a straight Euclidean line at constant speed, while B sees A moving in a straight Euclidean line at constant speed in the opposite direction. Given this abstraction and postulating the same observed speed of light for observers stationary in each of A and B results in the Lorentz transformation. The mathematics is elementary analytic geometry.

What is revolutionary are the effects, including time dilation. A sees B's clocks as running slower than his own, and B sees A's clocks as running slower than his own.

If A and B ever got back together and compared their clocks, the twin paradox would result. The twin paradox is not that the returning rocketeer is younger than his earthbound twin. This really happens. The twin paradox is that in special relativity, the twin in coordinate system A sees his brother in B aging more slowly, and the twin in B sees his brother in A aging more slowly.

But since coordinate systems A and B move steadily away from one another in Special Relativity, observers that are stationary in each never get back together again.

Special Relativity's relevance to physics was to establish the strongly non-intuitive consequences of its two simple postulates. General Relativity deals with the closer approximation to large scale physical reality by developing the laws of electrodynamics and motion in the more generalized arena of non-inertial coordinate systems: ones experiencing acceleration. The mathematics is a little more complicated, tensors instead of vectors, curved space instead of flat Euclidean space, etc.

Today's senior math undergraduate might say, "Well, it's just tensor calculus and differential geometry," and she would be right. What is revolutionary is not the math, but the effects of matter and motion upon the measurement of space and time.

Special Relativity is a special case of General Relativity--zero acceleration.The results of General Relativity continuously approach those of Special Relativity as you move toward less acceleration and flatter space. The two are mutually exclusive, in the sense that the postulates of Special Relativity are more restrictive, but they do not contradict one another.

To travel away, then return home and meet his older twin, the rocketeer must first accelerate to high speed, then turn around and come back to earth. Both speeding up and turning are accelerations. Special Relativity simply does not apply. Its first postulate, inertial coordinate systems, is violated. But the twin paradox doesn't occur. If the calculations of General Relativity are carried out, the traveler really is younger than his twin when he returns, as we see with traveling atomic clocks and cosmic rays.

It's been a long time since I read Gamow's "1, 2 3,…Infinity" as a high school freshman, but he was a highly qualified working physicist, and I doubt that he got anything wrong.

RNJ

P.S. I agree with Ricardo's take on dark matter.

P.P.S. This is not to say that the mathematical abstraction of inertial coordinate systems isn't useful. For example, the trajectories of intercontinental missiles are predicted using inertial coordinate systems, and the guidance systems used by these missiles use inertial coordinate systems. The error so induced is small compared to the uncertainties caused by the randomness of the atmosphere on reentry, and the uncontrolled error of the reentry aerodynamics of a vehicle that is in fact partly burning up.

You need detailed knowledge of geographical variations in the earth's gravitational field to achieve the accuracy that U.S. missiles do. But Newtonian dynamics in an inertial coordinate system are used in the calculations.
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 8 2014 23:10:58
 
Ruphus

Posts: 3753
Joined: Nov. 18 2010
 

RE: Richard and other thinkers (in reply to estebanana

Thank you for correcting me on dark matter.

I only heard about it from someone / have no clue myself. He said the way galaxies are behaving, and physical phenomenons like gravitational effects / centrifugal forces had to be reconsidered under formerly unknown characteristics introduced with dark energy and dark material.

I´ll tell him of you having blasted my bubble.

Ruphus
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 8:56:50
 
BarkellWH

Posts: 2893
Joined: Jul. 12 2009
From: Washington, DC

RE: Richard and other thinkers (in reply to Ricardo

quote:

So you can't really take special Relativity by it'self when you talk of space travel and TIME dilation effect and such. That is all a result of GENERAL theory of Relativity, the one that really matters with GPS and such as well.


Understood, Ricardo. Time dilation is a verified phenomenon under both Special Relativity (relative velocity time dilation) and general relativity (gravitational time dilation). In the theoretical example of a ship traveling into deep space at near light-speed, turning around and returning to Earth at near light speed to discover that many more years had elapsed on Earth than the time that had elapsed according to his ship's clock, however, I think is due more to the phenomenon of relative velocity time dilation (special relativity) than of gravitational time dilation (general relativity). Nevertheless, as a layman I cannot claim any authority and may well be mistaken here. But that is my take as I understand the issue.

So after an interesting and enlightening discussion of the possibility of time travel to the past and to the future, what is everyone's take on it? For my part, I think time travel to the past is impossible, both under the laws of physics and technologically. I think it impossible to travel back in time, insert one's self into the past, and influence it to attempt a different historical outcome.

Regarding time travel to the future, I think the old example of the near-light-speed traveler experiencing time dilation and returning to an Earth upon which much more time has elapsed than that experienced by the traveler is possible under the laws of physics, and may be technologically possible in the future (although I wouldn't place any bets on it happening any time soon!).

Cheers,

Bill

_____________________________

And the end of the fight is a tombstone white,
With the name of the late deceased,
And the epitaph drear, "A fool lies here,
Who tried to hustle the East."

--Rudyard Kipling
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 11:42:03
 
BarkellWH

Posts: 2893
Joined: Jul. 12 2009
From: Washington, DC

RE: Richard and other thinkers (in reply to BarkellWH

Appropriately, given our discussion, tonight (Sunday) begins a 13 part series on Fox cable at 9:00 PM EDT called "Cosmos: A Space-time Oddyssey." Apparently it is a revival, with new material, of Carl Sagan's "Cosmos: A Personal Voyage" that ran in 1980. The narrator is an astrophysicist, Neil deGrasse Tyson. I don't know how anyone could top Carl Sagan, The excitement and sense of wonder Sagan conveyed cannot be duplicated. But the subject matter is always interesting, and the new, updated "Cosmos" series should be well worth watching.

Cheers,

Bill

_____________________________

And the end of the fight is a tombstone white,
With the name of the late deceased,
And the epitaph drear, "A fool lies here,
Who tried to hustle the East."

--Rudyard Kipling
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 12:26:40
 
gmburns

Posts: 157
Joined: Nov. 20 2012
 

RE: Richard and other thinkers (in reply to BarkellWH

quote:

ORIGINAL: BarkellWH

Appropriately, given our discussion, tonight (Sunday) begins a 13 part series on Fox cable at 9:00 PM EDT called "Cosmos: A Space-time Oddyssey." Apparently it is a revival, with new material, of Carl Sagan's "Cosmos: A Personal Voyage" that ran in 1980. The narrator is an astrophysicist, Neil deGrasse Tyson. I don't know how anyone could top Carl Sagan, The excitement and sense of wonder Sagan conveyed cannot be duplicated. But the subject matter is always interesting, and the new, updated "Cosmos" series should be well worth watching.

Cheers,

Bill


Neil deGrasse Tyson is not only the most famous astrophysicist in the US, but he's also a good narrator. I wouldn't be worried about him considering his years of hosting on PBS.

_____________________________

Greg Mason Burns - Artist
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 13:10:09
 
Ricardo

Posts: 11363
Joined: Dec. 14 2004
From: Washington DC

RE: Richard and other thinkers (in reply to BarkellWH

quote:

ORIGINAL: BarkellWH

Appropriately, given our discussion, tonight (Sunday) begins a 13 part series on Fox cable at 9:00 PM EDT called "Cosmos: A Space-time Oddyssey." Apparently it is a revival, with new material, of Carl Sagan's "Cosmos: A Personal Voyage" that ran in 1980. The narrator is an astrophysicist, Neil deGrasse Tyson. I don't know how anyone could top Carl Sagan, The excitement and sense of wonder Sagan conveyed cannot be duplicated. But the subject matter is always interesting, and the new, updated "Cosmos" series should be well worth watching.

Cheers,

Bill


I think very little will be upgraded since Sagan's show. On one hand it's cool that we learned so much by the time Sagan made that program, on the other, it's a shame we have learned very little SINCE then...and no aliens yet, as that is the main point of the whole show. You just reminded me Bill that i had set up to record that show, thanks!

quote:

Regarding time travel to the future, I think the old example of the near-light-speed traveler experiencing time dilation and returning to an Earth upon which much more time has elapsed than that experienced by the traveler is possible under the laws of physics, and may be technologically possible in the future (although I wouldn't place any bets on it happening any time soon!).


Just to restate, we can make an ORION spacecraft with current technology. Budget and politics are the only constraints. It would travel fast enough to get us to near stars in life time of crew. Perhaps not return to experience "future earth", though the next generations could.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 14:12:21
 
Miguel de Maria

Posts: 3523
Joined: Oct. 20 2003
From: Phoenix, AZ

RE: Richard and other thinkers (in reply to Ricardo

It is kind of sad how little has been learned since the 70s, big-picture wise. I wonder if we're starting to find our limits. No fusion reactors, no men on Mars, no probes out of the solar system. String theory dead-ending, dark matter still in the dark. At least they found a neutrino.

Neil deGrasse Tyson is charismatic and will do a great job.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 15:19:46
 
Ruphus

Posts: 3753
Joined: Nov. 18 2010
 

RE: Richard and other thinkers (in reply to Miguel de Maria

quote:

ORIGINAL: Miguel de Maria

No fusion reactors, ...


What these guys in Cern did, at the risk of producing a black hole was plain nuts.
And like always, only worse than with nuclear reactors and its "disposing" of atomic waste, everyone sitting aside and watching bovine.

If it works, all power to the profiteers. If it won´t, let tax payers sort out the scraps.
And if it can´t be sorted out ( like actually nuclear waste already)?

If there be a more immediate issue like a cute little black hole now under Cern, what would the credo be?
"Oh, what to do now? Uhm, lets wait until the next legislature."
-

And while about the nuts mentality of major profiteers:
Look at the new hobbyhorse named fracking.
Is everyone really brain amputated to allow such insane ****?
How can there be missed out on what such procedure yields as future damages?
And don´t we know from experience already where the guys and their funds will be when landscapes desert from poisoned water and soil?

Ruphus
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 15:34:03
 
Miguel de Maria

Posts: 3523
Joined: Oct. 20 2003
From: Phoenix, AZ

RE: Richard and other thinkers (in reply to Ruphus

If it works, "free" energy for all!

Although you might share my cynicism that exploitation, greed, class stratification, status-seeking, barriers to advancement and equality--would be present even if humanity could gather more clean energy than they need.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 15:46:09
 
Ruphus

Posts: 3753
Joined: Nov. 18 2010
 

RE: Richard and other thinkers (in reply to estebanana

Definitely.
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 15:47:17
 
Ruphus

Posts: 3753
Joined: Nov. 18 2010
 

RE: Richard and other thinkers (in reply to estebanana

Besides ...

Could a yet little black hole kind of digged out and moved by extracting it including a great chunk of surrounding material?

I suppose the answer to be "no"; apart from the question of where to move the chunk anyway.

Ruphus
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 15:51:27
 
Richard Jernigan

Posts: 2681
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: Richard and other thinkers (in reply to Ricardo

quote:

ORIGINAL: Ricardo

Just to restate, we can make an ORION spacecraft with current technology. Budget and politics are the only constraints. It would travel fast enough to get us to near stars in life time of crew. Perhaps not return to experience "future earth", though the next generations could.



Ummm….

I have had the good fortune to watch a few rocket development programs up close. My brother was a NASA flight surgeon on the Gemini program, he was head of the Flight Medicine Branch throughout the Apollo moon landing program. The liquid fueled Saturn V rocket was an engineering masterpiece, but it was essentially scaling up mature technology that had already been developed into operational hardware.

I worked on Minuteman I, II and III, Peacekeeper, Trident I and Trident II, the British versions of Poseidon and Trident I, and other ballistic missile systems that I think I'm still not supposed to talk about.

I was Test Director at Kwajalein for the radar and telemetry components of Space-X's initial ventures. They intentionally adopted what might be considered one of the most primitive technologies, kerosene/liquid oxygen, to cut costs and development time. Still their first three launch attempts were spectacular failures, big explosions, the first of which destroyed their launch facilities.

Highly trained engineers and scientists at Kwajalein made fun of Space-X's spectacular accidents. I told them they were bound to happen. The question was, would they repeat their mistakes, or would they learn from them? They learned.

But compared to the spectacular failures of the intercontinental missiles and Saturn, Space-X's were toy rockets and the explosions were firecrackers.

Space-X has since moved on to much bigger rockets, scaling up the technology they developed at Kwajalein, and delivering cargo to the Space Station with an unmanned freighter. Elon Musk's signature project is now the Tesla automobile, but he told me and many others that he started Space-X because he wanted to see human interplanetary travel. They are still working on a manned vehicle design.

Each of these projects was eventually successful--or in the case of Space-X's manned effort, I think they have shown enough success that it will be--but along the way each experienced sharp departures from original plans and estimates. As someone said about pushing the envelope of big airliner design, "It's a sporty game."

I'm not saying the Orion concept will never work--whatever the Orion concept may be. The concept itself was still evolving rapidly when the project was cancelled. But I think you would have a hard time convincing even the protagonists of the Orion project that it was "current technology". There was a lot of work left to be done, and if experience is any indication, the end result would have been a good deal different from the starting ideas.

It's true that it was the Test Ban Treaty that drove a stake through the heart of Orion. But there were a lot of very big technical hurdles remaining to be overcome. Saying it was only politics and economics that killed Orion is a little like saying that if we cured cancer, the 25% of people who now die from it would live forever.

Now I will take the time to apologize for my trenchant tone. It is offensive to most people to be contradicted, and if I have offended anyone, I apologize.

Engineers and scientists learn that everybody makes mistakes, and that it is their duty to speak up if they think someone has. Engineers and scientists learn to be grateful for being contradicted, if it saves them from a mistake, or if it gives them the opportunity to clarify their thinking. The tone of debate in engineering and science probably sounds impolite at times to non-members of the culture. It generally is not. It's the way we work.

For several years two of the five blackboard panels in my office at Kwajalein were densely covered with a calculation, line after line of calculus. Often enough to make it worthwhile, a new engineer would give me the opening i was waiting for. As our conversation turned from business to chat, one bright young man said, indicating the board, "Gee, I want to learn how to do that."

I told him what the calculation was about. I said I showed it to two of the best guys who ever worked for me. They told me it was wrong. I went through the calculation with them. They didn't argue. The error wasn't immediately obvious--besides, I was the boss. But the next day they came back and showed me experimental data that definitively refuted my conclusion. I kept the erroneous calculation on the board as a souvenir.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 19:18:03
 
Richard Jernigan

Posts: 2681
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: Richard and other thinkers (in reply to estebanana

General Relativity deals not only with the effects of mass-induced gravity and relative velocity, but also with the effects of any acceleration whatsoever of a coordinate system.

One of the classic exercises assigned to students involves an isolated space station built in the shape of a spoked wheel, rotating far enough away from any other mass to be unaffected by mass-induced gravity.

An observer outside the space station, but at rest relative to its center, observes a space station passenger making measurements of the length of a spoke and of the circumference of the space station, and concludes that the circumference of a rotating circle is not equal to pi times its diameter.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 20:29:47
 
aeolus

Posts: 765
Joined: Oct. 30 2009
From: Mier

RE: Richard and other thinkers (in reply to estebanana

quote:

Kwajalein


Has the installation at Kwajalein ever intercepted an incoming missile?

I was lucky to watch the NASA feed live of the repair to the Hubble Space Telescope and seeing how huge were the space suits and how tedious the effort to remove a few screws for which it was reported that the crew trained for 18 months underwater to carry out the mission I was left with the understanding of just how hostile is outer space to humans. Still that should be no deterrent to persist in say a one way voyage to Mars. I read there are plenty of applicants for the ride.

I well well remember seeing Spudnik as no more than a moving point of light illuminated by the sun low on the horizon in SA and the traumatic effect on the US psyche and the numerous failures at launching a rocket to catch up with the Russians. The gold plated lunar landing craft on display in DC stands as tribute to the engineers who labored so diligently to make it happen.
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 20:35:48
 
BarkellWH

Posts: 2893
Joined: Jul. 12 2009
From: Washington, DC

RE: Richard and other thinkers (in reply to Richard Jernigan

quote:

Still their first three launch attempts were spectacular failures, big explosions, the first of which destroyed their launch facilities.


Those who criticize America's efforts to develop rocketry and missiles, from manned space flight to "Star Wars" and ballistic missile interceptors, because of persistent failures, should read Tom Wolfe's great book on the Mercury Project, "The Right Stuff," which came out in 1978. Wolfe's book is a tribute to the initial seven astronauts chosen for Project Mercury. But among the most interesting and relevant subjects he brings up is how many failures occurred before the Mercury Project was ready for manned flight. Our rockets were literally blowing up on the launch pad and after launch. They were blowing up spectacularly. But NASA persisted and finally refined the rockets to the point where manned flight became the reality. The takeaway, as I see it, is that just because a particular project may have failed to date is no reason to abandon it if it is considered important. Try and Try again, constantly refining the technology until it works as intended.

Cheers,

Bill

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With the name of the late deceased,
And the epitaph drear, "A fool lies here,
Who tried to hustle the East."

--Rudyard Kipling
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 9 2014 22:09:43
 
Richard Jernigan

Posts: 2681
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: Richard and other thinkers (in reply to aeolus

quote:

ORIGINAL: aeolus

quote:

Kwajalein


Has the installation at Kwajalein ever intercepted an incoming missile?



I no longer have ready access to the archives, but at a guess, at least a dozen times. The project I was personally involved with in the late 1990s and early 2000s had a score of five hits out of eight tries. These were exoatmospheric intercepts of missiles launched from California, 7,000 miles away. It ended with a string of at least three successes, indicating that the faults/mistakes discovered earlier had been corrected. This is an excellent record for a big advanced technology project.

When you fire up the prototype of a new radar, command the antenna to steer left and it goes right, nobody is particularly surprised. I've seen it happen more than once. But when you blow up a big rocket, destroy the entire launch complex in a giant ball of flame and light up the countryside for miles around as though the sun were coming up, word tends to get out.

Wait, I'll add at least three to the total. We acquired some actual Scud missiles, from a source which will remain nameless. We launched them from another atoll to the east, aimed at the ocean just short of Kwajalein. They were intercepted by actual U.S. Army operational Patriot missile units on Kwajalein, not by us techno hot-shots. They batted 1000--shot down all of them, for any non-baseball fans.

Since I left Kwaj there has been at least one successful test of the U.S. Navy's ship based system, shooting down an intercontinental missile launched from California. This is the system that the Russians don't want us to install in ground based form in Poland.

I know some of my good friends have been involved in a project to launch missiles from Alaska, aimed for the ocean just off California, to be shot down by inerceptors launched from Vandenburg Air Force Base just northwest of Santa Barbara, but I haven't kept track of the details.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 10 2014 0:52:13
 
Arash

Posts: 4405
Joined: Aug. 9 2006
From: Iran (living in Germany)

RE: Richard and other thinkers (in reply to Ricardo

quote:

ORIGINAL: Ricardo


There used to be a theory of universe evolution that space-time might be slowing expansion and therefore might either slow forever never stoping, or it might stop and stay that way, or, because of gravity, REVERSE .... eventually coming back to a singularity. THey called this "big crunch". This process would mean "unrolling" as you say, experienced by everyone and everything. It is illustrated in Hawkings "brief history of time". Observation shows accelerated expansion, so that Big Crunch idea has been dropped by most.



It is still unknown what dark energy really is and how it will evolve in future (thus if the universe will expand till big rip or chill). Its the current observation. But as we know we had other phases with opposite effects in the past already (expansion slowing down), so this can change (for whatever reason).

Everything which we don't have any clue about starts with "dark" or "big" anyway.

So there are still other possibilities such as the cyclic models (such as big bounce). With the concept of quantized Spacetime in to planck level and loop quantum gravity/cosmology, the problems of Infinite density and singularities which contradict quantum mechanics and relativity can both be somehow "solved". There would be finite mass/energy in spacetime "atoms" with a finite size. That would lead to a universe prior to ours with some sort of "inverted" spacetime.

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  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 10 2014 4:16:08
 
duende

Posts: 3051
Joined: Dec. 15 2003
From: Sweden

RE: Richard and other thinkers (in reply to estebanana

This is intressting.

The elegant universe.



Part 1

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This is hard stuff!
Don't give up...
And don't make it a race.
Enjoy the ray of sunshine that comes with every new step in knowledge.

RON
  REPORT THIS POST AS INAPPROPRIATE |  Date Mar. 10 2014 5:32:02
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