Who thinks Faster Than Light travel is possible?

[Rufus Coppertop]

Each ball takes half a year to travel to a point that is half a light year away. The light from each ball then takes half a year to travel back to the origin. If I observe the objects after one year, I see them half a light year away from me.

Aaaaaah!

Okay. I get what you're saying. After a year, we're looking at light that is six months old. It makes perfect sense. What I don't get though, is the concept that the ball really is only half a light year away considered from its own point of view.

If we imagine that Auntie Dorris has just hung out her washing on a space station one light year away and one of the balls knocks her knickers off the line a year later and she rings up on a magic telephone that can transmit messages instantly, she'll surely be shouting "Oi! Knock that off!" a year later, won't she?

And when she does, we'll know that the ball actually travelled a full light year in that year even though it looks to us as if it's only halfway to her knickers.

 

[Wayne Mack]

Let's do a thought experiment... you are you in your own frame of reference in time and space. You then go faster and faster as you say until you exceed the speed of light and realise you are seeing your friend ten minutes ago. You then continuing at a speed greater than light turn around and go an tap Albert and yourself on the shoulders. But your earlier you never felt those taps. The question is why not?

Or putting it another way, if things are travelling faster than the speed of light, why aren;t we experiencing them?

Okay, I'll play. The part about Albert confused me, so I'll omit him. Assuming the frame of reference accelerates to the speed of light and then goes past it, the observer would see time slow and then stop. Assuming negative time, the observer would move back to earlier times. One cannot assume the observer both moves forward in time and backwards in time, so the observer cannot create new events. The observer would be walking back through past events.

From an external frame of reference, when the moving object starts going backwards in time, then it no longer goes forward in time. From an external point of view, the object would hit the speed of light and then cease to exist. From an external point of view, the speed of light was not violated, though there is the pesky matter of conservation of matter and energy.

 

[Christine Wheelwright]

If we imagine that Auntie Dorris has just hung out her washing on a space station one light year away and one of the balls knocks her knickers off the line a year later and she rings up on a magic telephone that can transmit messages instantly, she'll surely be shouting "Oi! Knock that off!" a year later, won't she?

No. Because her voice down the phone line must also travel at less than the speed of light. If I was the one that threw the ball, I will hear her after two years telling me that the ball is at her position one light year away.

The point is, there is no omniscient observer who sees the true position of everything at a fixed point in time. There is no fixed point in time. Time is not independent of space. So, I think in a very real sense, the object is indeed where I observe it after one year; half a light year away. Its effects on me are the effects of an object half a light year away. I can mathematically extrapolate a different position for it if that makes me happy (knowing that I am looking back in time). But I'm not sure how useful this is. I'm sure this kind of extrapolation is used in calculations of the 'present' size of the universe.

From the object's point of view, the origin point appears to be frozen in time because light from the origin has travelled alongside it. Looking back, it still sees me standing there, my arm extended as I throw it. As if time has stood still. Time therefore slows down (relative to the origin) for objects as they get faster relative to the origin point. Time stops when the speed of light is reached.

 

[Christine Wheelwright]

Okay, I'll play. The part about Albert confused me, so I'll omit him. Assuming the frame of reference accelerates to the speed of light and then goes past it, the observer would see time slow and then stop. Assuming negative time, the observer would move back to earlier times. One cannot assume the observer both moves forward in time and backwards in time, so the observer cannot create new events. The observer would be walking back through past events.

From an external frame of reference, when the moving object starts going backwards in time, then it no longer goes forward in time. From an external point of view, the object would hit the speed of light and then cease to exist. From an external point of view, the speed of light was not violated, though there is the pesky matter of conservation of matter and energy.

[Redacted. I had an incorrect explanation of time dilation in here]

 

[Mon0Zer0]

A short summary of the thread so far:

1. The Hard-science Hardliners assure the public that our current understanding of physics is good and complete enough to preclude any changes to our understanding that C is an absolute limit. (Despite current physics also telling us that the vast majority of the universe is made of matter and energy we can neither find nor define.)

You don't need our current understanding of physics to be complete or good. In order to assume something exists there must be evidence. See Russel's teapot.

Physicists don't assume dark matter exists, they posit as a potential solution to the evidence of inflation. There's a high probability they're wrong.

There's nothing within the models that suggests ftl travel exists, nor have we seen evidence of it. We've only seen evidence that c is the limit of causality. Should we see or find models that suggest otherwise we can update our understandings accordingly.

3. The Maybes, who are probably dirty agnostics in their private lives as well.

Dirty agnosticism is where it's at, baby!

 

[Christine Wheelwright]

From the object's point of view, the origin point appears to be frozen in time because light from the origin has travelled alongside it. Looking back, it still sees me standing there, my arm extended as I throw it. As if time has stood still. Time therefore slows down (relative to the origin) for objects as they get faster relative to the origin point. Time appears to stop at the origin when the speed of light is reached relative to it.

I should add that time can appear accelerated at an object as I move towards it (or as the object moves towards me....basically the same thing in a relativistic universe). An object moving towards me can even appear to be moving at faster than the speed of light because of this effect.

There is also an effect known as time dilation which is not the same as that described above.

 

[Swank]

You don't need our current understanding of physics to be complete or good. In order to assume something exists there must be evidence. See Russel's teapot.

Physicists don't assume dark matter exists, they posit as a potential solution to the evidence of inflation. There's a high probability they're wrong.

There's nothing within the models that suggests ftl travel exists, nor have we seen evidence of it. We've only seen evidence that c is the limit of causality. Should we see or find models that suggest otherwise we can update our understandings accordingly.



Dirty agnosticism is where it's at, baby!

I don't think FTL exists, I just don't think it should be ruled out at this stage. Especially by SF writers. Along with all the other unlikely but not actually disprovable stuff that they might dote upon.

 

[Christine Wheelwright]

I don't think FTL exists, I just don't think it should be ruled out at this stage. Especially by SF writers. Along with all the other unlikely but not actually disprovable stuff that they might dote upon.

Absolutely. It is often said the purpose of SF is to ask 'what if?' rather than attempt to accurately predict the future. I personally do not think we will reach the stars, but by all means we should write about starships. For entertainment, and through entertainment to explore the universe and the human spirit (its strengths and frailties).

 

[Extollager]

Absolutely. It is often said the purpose of SF is to ask 'what if?' rather than attempt to accurately predict the future. I personally do not think we will reach the stars, but by all means we should write about starships. For entertainment, and through entertainment to explore the universe and the human spirit (its strengths and frailties).

Sure, but also it might be appropriate for the sf community to be a bit more visible with the point of view you have expressed, i.e. that the science we actually have discourages the popular expectations of FTL travel, the development of psionic powers, time travel, the existence of life off the earth and even of contact with extraterrestrial civilizations, and so on. It might not hurt if we were a bit more visibly capable of distinguishing between our favorite entertainment genre and our sense of what is probable.

Here are some polls that were easy to find that suggest popular notions are at odds with the science we actually have. I suspect a lot of this is due to the immersion of popular culture in sf tropes. I also included an article from National Geographic about living on Mars.

Do Americans Believe in UFOs?

UFOs could be anything from figments of the imagination to cases of mistaken identity to alien spacecraft. Learn what Americans think on the issue.

news.gallup.com

Poll: 25 Percent Believe Time Travel Will Happen Before Female Parity in Fortune 500

www.nysscpa.org

Is there life on other planets? Here’s what Americans think | YouGov

Recent data from a YouGov poll of more than 7,000 US adults finds that nearly half (47%) believe that there are basic life forms on other planets within our solar system.

today.yougov.com

Will Humans Ever Colonize Other Planets? They Should.

Futurist Michio Kaku sees humans doing ballet on Mars and projecting their brains into the cosmos. And aliens? Oh, they're coming.

www.nationalgeographic.com

 

[Swank]

Sure, but also it might be appropriate for the sf community to be a bit more visible with the point of view you have expressed, i.e. that the science we actually have discourages the popular expectations of FTL travel, the development of psionic powers, time travel, the existence of life off the earth and even of contact with extraterrestrial civilizations, and so on. It might not hurt if we were a bit more visibly capable of distinguishing between our favorite entertainment genre and our sense of what is probable.

Here are some polls that were easy to find that suggest popular notions are at odds with the science we actually have. I suspect a lot of this is due to the immersion of popular culture in sf tropes. I also included an article from National Geographic about living on Mars.

Do Americans Believe in UFOs?

UFOs could be anything from figments of the imagination to cases of mistaken identity to alien spacecraft. Learn what Americans think on the issue.

news.gallup.com

Poll: 25 Percent Believe Time Travel Will Happen Before Female Parity in Fortune 500

www.nysscpa.org

Is there life on other planets? Here’s what Americans think | YouGov

Recent data from a YouGov poll of more than 7,000 US adults finds that nearly half (47%) believe that there are basic life forms on other planets within our solar system.

today.yougov.com

Will Humans Ever Colonize Other Planets? They Should.

Futurist Michio Kaku sees humans doing ballet on Mars and projecting their brains into the cosmos. And aliens? Oh, they're coming.

www.nationalgeographic.com

These polls strike me as having less to do with the impact of SF on culture and much more to do with critical thinking skills and the prevalence of magical and conspiratal thinking.

Even without SF, the human mind revisits past events and tries to re-do them, tries to insert itself into the minds of others through empathy, offers dreams of flying and treats impossibly distant places as imaginable. No wonder we think about time travel, ESP, super powers and FTL. They fit our mental biases.

 

[Wayne Mack]

[Redacted. I had an incorrect explanation of time dilation in here]

Aside. I have found that I can delete quoted (or replied text) by simply deleting all of the text within the reply block. Of course, this has to be done within the edit time period, but I have used that to make a reply just go away.

 

[Extollager]

Swank wrote, "These polls strike me as having less to do with the impact of SF on culture and much more to do with critical thinking skills and the prevalence of magical and conspiratal thinking."

In a culture saturated with sf movies, games, TV shows, etc., science fiction will be likely to influence the forms conspiracy theorizing and magic thinking take. Sf can be an enabler of these.

 

[Christine Wheelwright]

Sure, but also it might be appropriate for the sf community to be a bit more visible with the point of view you have expressed, i.e. that the science we actually have discourages the popular expectations of FTL travel, the development of psionic powers, time travel, the existence of life off the earth and even of contact with extraterrestrial civilizations, and so on. It might not hurt if we were a bit more visibly capable of distinguishing between our favorite entertainment genre and our sense of what is probable.

Here are some polls that were easy to find that suggest popular notions are at odds with the science we actually have. I suspect a lot of this is due to the immersion of popular culture in sf tropes. I also included an article from National Geographic about living on Mars.

Do Americans Believe in UFOs?

UFOs could be anything from figments of the imagination to cases of mistaken identity to alien spacecraft. Learn what Americans think on the issue.

news.gallup.com

Poll: 25 Percent Believe Time Travel Will Happen Before Female Parity in Fortune 500

www.nysscpa.org

Is there life on other planets? Here’s what Americans think | YouGov

Recent data from a YouGov poll of more than 7,000 US adults finds that nearly half (47%) believe that there are basic life forms on other planets within our solar system.

today.yougov.com

Will Humans Ever Colonize Other Planets? They Should.

Futurist Michio Kaku sees humans doing ballet on Mars and projecting their brains into the cosmos. And aliens? Oh, they're coming.

www.nationalgeographic.com

Yes, exactly. You have hit on one of my pet topics. The scientifically illiterate public (if that isn't too arrogant a phrase) has way too much optimism and way too much faith in science and technology. And I speak as a scientist.

I cringe whenever some know-nothing (like, say, Elon Musk) pops up with his latest nonsense about AI-enabled self-driving robo-taxis or manned Mars missions in a handful of short years. People lap that stuff up, and they don't seem to notice when it doesn't happen. They just keep sticking their hands in the flames. The danger, of course, is that complacency results when it comes to humanity's very real problems; like climate change. There is an irrational belief that some 'invention' by some 'genius' will save us and that everything will be ok. Of course, the situation is made even worse by all these ridiculous announcements and investment-seeking cgi videos from start-ups claiming to have made new discoveries that will 'revolutionize' everything. All just scams. But it is comforting for folks to assume science and technology will save us.

 

[Extollager]

I think too that the public sometimes gets the impression that the scientific knowledge we actually have isn't all that interesting; it's what scientists might discover and what might then be its applications that are of interest. Surely that's not really true. Can't there be some other "narrative"? For example, let's look at what has been accomplished lately in regard to space-based telescopes, or actually landing on a comet, etc., with the budgets that supported these successes -- i.e. tiny amounts (relative to what's spent on many costly non-science programs and agencies). Some sciences don't seem to get much responsible attention at all, e.g. archeology.

 

[Mon0Zer0]

I think too that the public sometimes gets the impression that the scientific knowledge we actually have isn't all that interesting; it's what scientists might discover and what might then be its applications that are of interest. Surely that's not really true. Can't there be some other "narrative"? For example, let's look at what has been accomplished lately in regard to space-based telescopes, or actually landing on a comet, etc., with the budgets that supported these successes -- i.e. tiny amounts (relative to what's spent on many costly non-science programs and agencies). Some sciences don't seem to get much responsible attention at all, e.g. archeology.

The future is always exotic. The present, prosaic. We routinely use technology our great grandparents would have been astounded by. It's so much easier to get worked up over travel to Kepler-22b than it is half way around the globe, yet the latter is a miracle in human history. Quite sad, really.

 

[AllanR]

with the budgets that supported these successes -- i.e. tiny amounts (relative to what's spent on many costly non-science programs and agencies)

Like India launching a probe to Mars the same year Interstellar came out, and they did it cheaper than the cost of the movie. $57 million vrs $165 million

 

[Swank]

I wouldn't say our society is saturated with SF. Super hero movies do well, otherwise it's pretty niche.

 

[Ursa major]

Super hero movies

...are fantasy, not SF.

 

[asp3]

At this point in time I think it is possible but also think my opinion comes from a state of ignorance. I don't think I know enough to have an opinion of any value.

 

[Extollager]

...are fantasy, not SF.

Of course superhero movies are fantasy, but they are usually presented with an "sf" framework. As someone who's watched quite a few of the Marvel ones (but none in the past three years or so), I'm confident about saying that. Thor, the Avengers, the Guardians of the Galaxy, Black Panther... they zip around in spaceships or the like, turn on force fields, use hi-tech blasters, that sort of thing. Their enemies may include "aliens." All of these are much more "SF" than, say, the LotR movies, which are indeed fantasy. Even Dr. Strange is a guy who navigates "other dimensions," etc.; the Marvel franchise would allow that you could get to some, at least, of those "mystic realms" by super-technology, I suppose.

Sure, we might well define these entertainments as fantasy and not sf, but they use sf tropes and certainly contribute to the constant streaming of sfnal imagery and expectations in popular consciousness.