Pentagon releases UFO videos

[GGG]

Originally Posted by Fuzz

When your theories on aliens sound so outlandish you have to go with something more believable, like time travelers.

I’d argue time travel is more likely than an alien as they know where we are and requires only time travel to be invented before we destroy ourselves.

That’s a far lower barrier then the other option

[Fuzz]

Is there any theory that allows traveling back thorough time based on what we know? I thought any reasonable theory around time travel conforms to general relativity, in that you would only be able to slow time for yourself, thus appearing to have traveled through time. Logically, I don't know how you can come up with a theory to travel backwards. Practically, once that ability exists, I don't know how we would be blind to it. So I'm actually more on the "aliens" side.

[FlamesAddiction]

Originally Posted by Fuzz

Is there any theory that allows traveling back thorough time based on what we know? I thought any reasonable theory around time travel conforms to general relativity, in that you would only be able to slow time for yourself, thus appearing to have traveled through time. Logically, I don't know how you can come up with a theory to travel backwards. Practically, once that ability exists, I don't know how we would be blind to it. So I'm actually more on the "aliens" side.

Yeah, the theories I have read described theoretical time travel more as a rewind than actually being able to navigate it. Living things could only move backwards in time if they already existed in that time and wouldn't be able to change events. Objects could only go back to the point that time travel was invented because you can't change events in the past that weren't already changed in the future (if that makes sense).

Time travel is just highly theoretical and mostly a mind experiment. I don't think most physicists think it is possible at all (expect for moving forward through time at our current rate of course).

[troutman]

If time travel were possible, the earth travels very far in space over time.

https://www.newscientist.com/lastwor...our-lifetimes/

Movement through space is a big problem for time travel. Assuming you can get past the trivial bit of transporting yourself 66 years into the past, you would then be trillions of kilometres from the spot on the planet that you started from.

[Lanny_McDonald]

General relativity allows for "time travel". This is not a three dimensional problem, it is a four dimensional problem. Just like we can run computer simulations to pinpoint the location of heavenly bodies in the past and future, general relativity provides a means to warp space and time to connect those locations.

[jayswin]

^^^^

Yep. Whether we can do it or not will likely not hinge on how far or when something happened and being able to "find" it.

[Snuffleupagus]

Originally Posted by Lanny_McDonald

General relativity allows for "time travel". This is not a three dimensional problem, it is a four dimensional problem. Just like we can run computer simulations to pinpoint the location of heavenly bodies in the past and future, general relativity provides a means to warp space and time to connect those locations.

Time travel might be theoretically possible but unless you're talking micro seconds it's still just science fiction and like traveling the speed of light it will never be achieved with matter especially living matter.

Fun to think about though, there's the paradox problem like in "back to the future", go back in time to set up your parents so you can be born.

Personally I think if something happened, it happened and can't be changed.

[Fuzz]

Alt-text "ALERT: Human 910-25J-1Q38 has created a Youtube channel. Increase erratic jerkiness of flying by 30% until safely out of range."


It's a fair point...

[photon]

There's an XKCD for everything.

[Lanny_McDonald]

Originally Posted by Snuffleupagus

Time travel might be theoretically possible but unless you're talking micro seconds it's still just science fiction and like traveling the speed of light it will never be achieved with matter especially living matter.

Depends on the possible technology. Yes, if you are exposing a living creature to extreme gravity it is likely to be torn apart. But in the vacuum of space is there gravity to tear the creature apart when travelling at the speed of light? What if you're not traveling at the speed of light, but instead using gravity to bend space from a distant point and bringing it to you?

Also, if you are creating the gravity field around the creature, then the gravity within the bubble remains constant and the creature is then unaffected while the space around the gravity field is bent. You are thinking about the effect of the earth's gravity impacts us, rather than trying to understand that the force of the gravity happens outside of the envelope impacting the creature. Gravity impacts the space around the creature, not on the creature.

Fun to think about though, there's the paradox problem like in "back to the future", go back in time to set up your parents so you can be born.

Only if you believe in there being only one timeline in space time.

Personally I think if something happened, it happened and can't be changed.

That's okay. I'm kind of the same way myself. But I can't help but think of the potential for other possibilities. There are many concepts that propose alternate dimensions and parallel universes, which can then explain our experiences/ability for premonition, or deja vu, or even reincarnation. What we actually know about the universe around us is infinitely small to what we think we know. In another 100 years people will look back at what we think we knew and shake their heads.

[Ozy_Flame]

Originally Posted by Lanny_McDonald

Depends on the possible technology. Yes, if you are exposing a living creature to extreme gravity it is likely to be torn apart. But in the vacuum of space is there gravity to tear the creature apart when travelling at the speed of light? What if you're not traveling at the speed of light, but instead using gravity to bend space from a distant point and bringing it to you?

To this point, I think the tic-tac technology - and ultimately any vehicles that could hit Mach 13-15 with human occupants - would ultimately need to compress matter infront of the vehicle and expand it behind.

Essentially the vehicle isn't moving at those speeds; it's "pinching" through the space around it. Effectively this is an Alcubierre Drive, although likely not realistic to build one (for a variety of reasons). That said, I don't think it's technically impossible.

[Snuffleupagus]

Originally Posted by Lanny_McDonald

Depends on the possible technology. Yes, if you are exposing a living creature to extreme gravity it is likely to be torn apart. But in the vacuum of space is there gravity to tear the creature apart when travelling at the speed of light? What if you're not traveling at the speed of light, but instead using gravity to bend space from a distant point and bringing it to you?

Also, if you are creating the gravity field around the creature, then the gravity within the bubble remains constant and the creature is then unaffected while the space around the gravity field is bent. You are thinking about the effect of the earth's gravity impacts us, rather than trying to understand that the force of the gravity happens outside of the envelope impacting the creature. Gravity impacts the space around the creature, not on the creature.

The only thing science can see that comes close to the extreme gravity your talking about is the event horizon around a black hole and the gravity from a neutron star and both of those tear complete stars to nothing but radiation, to think a living creature could survive this is complete science fiction from a comic book.

Originally Posted by Lanny_McDonald

Only if you believe in there being only one timeline in space time.

Again, science fiction.

Originally Posted by Lanny_McDonald

That's okay. I'm kind of the same way myself. But I can't help but think of the potential for other possibilities. There are many concepts that propose alternate dimensions and parallel universes, which can then explain our experiences/ability for premonition, or deja vu, or even reincarnation. What we actually know about the universe around us is infinitely small to what we think we know. In another 100 years people will look back at what we think we knew and shake their heads.

We've come a long ways in the last 100 years, perfected powered flight, put men on the moon and even harnessed the power of the atom but what we didn't do was break the laws of physics that peering into the universe has taught us.

[Superflyer]

Originally Posted by Fuzz

When your theories on aliens sound so outlandish you have to go with something more believable, like time travelers.

That sounds like a movie.

10,000 years ago humans abandoned Earth because we abused it do much. We had to go to a new planet in a neighboring solar system that could sustain us, leaving behind much of what we knew and had.
Present day, a rag tag group of university students while playing in the lab one day discover time travel. To learn more about their history they travel back to when we left Earth, With modern technology, they were ready for the travel, what they were not ready for, was love!

[Matata]

Originally Posted by Snuffleupagus

[...]

We've come a long ways in the last 100 years, perfected powered flight, put men on the moon and even harnessed the power of the atom but what we didn't do was break the laws of physics that peering into the universe has taught us.

It's very hard to conceptualize where technology will be in another 100 years, impossible to conceptualize where it will be in a million years. If we are contacted by aliens, it's pretty likely their civilization is on the scale of being millions to billions of years older than our own. We can't even begin to guess what their limitations are.

[FlamesAddiction]

Originally Posted by Superflyer

That sounds like a movie.

10,000 years ago humans abandoned Earth because we abused it do much. We had to go to a new planet in a neighboring solar system that could sustain us, leaving behind much of what we knew and had.
Present day, a rag tag group of university students while playing in the lab one day discover time travel. To learn more about their history they travel back to when we left Earth, With modern technology, they were ready for the travel, what they were not ready for, was love!

Oh bow bow! Ohhhh Yeahhhhhhh! Chick Chicka chicka.

[Lanny_McDonald]

Originally Posted by Snuffleupagus

The only thing science can see that comes close to the extreme gravity your talking about is the event horizon around a black hole and the gravity from a neutron star and both of those tear complete stars to nothing but radiation, to think a living creature could survive this is complete science fiction from a comic book.

Not science fiction. Science fact according to Einstein. But why listen to that goober?

We've come a long ways in the last 100 years, perfected powered flight, put men on the moon and even harnessed the power of the atom but what we didn't do was break the laws of physics that peering into the universe has taught us.

What is being talked about actually complies with the laws of physics. Einstein is the one who suggested it and supported it with his theory of relativity. Just because you don't understand something does not mean it is not possible or does not comply with the laws of physics. There's a lot more to the world than the very small slice of knowledge you possess. When we speak to the universe, that slice doesn't even register because you can't even comprehend what we don't know and continue to suggest we do know that which scientists have admitted they don't know.

[jayswin]

Originally Posted by Snuffleupagus

We've come a long ways in the last 100 years, perfected powered flight, put men on the moon and even harnessed the power of the atom but what we didn't do was break the laws of physics that peering into the universe has taught us.

In the last 100 years, yes. Not really speaking specifically to this debate but what we learn in the next 100 years will probably dwarf and discredit (or expand upon greatly) a lot of what we learned in the last 100 years. The exponential growth of understanding and exploration of our universe is just absolutely mind blowing. To suggest that "we learned this much in 100 years and didn't do something, so therefore..." works in 2021, I guess. But ultimately the last 100 years is a blip and in the infancy of understanding our universe.

It's a very special time to be alive in that respect.

[Snuffleupagus]

Originally Posted by Lanny_McDonald

Not science fiction. Science fact according to Einstein. But why listen to that goober?



What is being talked about actually complies with the laws of physics. Einstein is the one who suggested it and supported it with his theory of relativity. Just because you don't understand something does not mean it is not possible or does not comply with the laws of physics. There's a lot more to the world than the very small slice of knowledge you possess. When we speak to the universe, that slice doesn't even register because you can't even comprehend what we don't know and continue to suggest we do know that which scientists have admitted they don't know.

Maybe I missed something on the works of Einstein but where did he ever suggest it's possible for a living being to survive traveling at the speed of light in order to time travel? all he said was it's theoretically possible if one could travel faster than light but he didn't mention how or how to survive it.

With much arrogance you apparently think I'm a pea brain so please explain to me what can travel at or even near the speed of light that contains mass?

Wormholes,folding space..etc is science fiction until proven

[GGG]

Originally Posted by Snuffleupagus

Maybe I missed something on the works of Einstein but where did he ever suggest it's possible for a living being to survive traveling at the speed of light in order to time travel? all he said was it's theoretically possible if one could travel faster than light but he didn't mention how or how to survive it.

With much arrogance you apparently think I'm a pea brain so please explain to me what can travel at or even near the speed of light that contains mass?

Wormholes,folding space..etc is science fiction until proven

It’s not science fiction when there is a theoretical basis for it. It’s theory that can’t be tested with current technology. There is a difference.

The simplest way to state it is that general relativity does not prohibit geometries of space time that permit time travel.

The rest is an energy problem rather than a how do you violate the laws of the universe problem.

The most famous is the Eisenstein Rose Bridge ie wormholes.

https://en.m.wikipedia.org/wiki/Wormhole

[Fuzz]

Theoretically possible? Possibly.
Practically possible? Probably not.