What is more plausible/likely, Aliens or Time Travelers?

I personally think future human time travelers are more likely than aliens visiting earth, given the sheer distance between solar systems.

However. If you can travel through time, you likely also have the ability to travel through space because at some point in physics space and time become spacetime. Spacetime is one. So, time travel is the same as space travel because they’re one.

Here’s an example. There’s a thing called time-dilation as you increase speed and distance from earth. The closer you get to the speed of light, the farther you get from earth, and the slower time moves for you relative to you. However, back on earth, time is moving much faster. I don’t remember the actual numbers but the time that passes on earth relative to you traveling through space is orders of magnitude greater. Here’s a quote from AMNH.

“Five years on a ship traveling at 99 percent the speed of light (2.5 years out and 2.5 years back) corresponds to roughly 36 years on Earth.”

So you would have only traveled for 5 years, but 36 years would have passed on earth, meaning everyone you know would be very old or dead and a new generation would have emerged.

This is the biggest reason I’m beginning to think that there may be no interstellar aliens.

Special relativity makes interstellar travel inefficient and purposeless. In the amount of time that passes on your home world while you astronaut travels to the nearest star system and back, generations would pass, and your astronaut would only be a few years older (if they return). Which defeats the purpose of leaving the planet to begin with because of the advancement of technology during that time.

Think about it. If our astronaut travelled 2.5 years out and 2.5 years back at 99.9999% the speed of light, and those on earth aged 36 years, then how far would technology have advanced in that 36 year period? Would it have advanced enough to develop FTL (faster than light travel? You see what I’m getting at.

We are nowhere near developing anything even remotely close to SOL (speed of light) travel. But we might get closer in the next 36 years. Right?

Speed of light travel is irrelevant. At that point it’s TIME travel no matter how you look at it.

Aliens would have the same limitations. These limitation are not only dictated by the physics, but the speed of their advancement of technology.

It all leads to the same place; I think all intelligent civilizations go through this stage of learning and technological advancement. I think they realize eventually with their discovery of special relativity, that interstellar travel is pointless; at least relative to those left on their home world.

Why not just wait? Instead of trying in vain to develop interstellar SOL or FTL travel, simply wait and develop time travel instead, which is technically the same thing. If you can control time you can control space because time and space are one when they become spacetime.

It would be POINTLESS to try to send your astronauts to another start system and come back because by the time they came back, generations would have passed on the home world, making the whole thing a moot point. Sure there would be some scientific knowledge gained, of course.

But by the time they develop SOL or FTL travel and sent astronauts to the nearest start system and back, they will most likely have developed time travel.

You see what I’m saying?

I think “aliens” are BOTH. Aliens are time travelers because they have to be to travel between star systems.

More importantly, since spacetime is one, I think if these aliens exist, that they have developed technology beyond the SOL and FTL stages of advancement, and they likely realized that propulsive interstellar travel is pointless; and also realized that transporting their astronauts through some kind of portal system (wormhole) which instantly transports them from one system to another is much more plausible and may solve the time dilation problem.

If they instantly transport themselves from one location in the galaxy to another, and back to their home planet, theoretically does that mean that no time will have passed? Could they essentially dial in a time and spatial coordinate, hit a button and instantly travel through time and space?

This is how I see it happening. If time and space are one, and wormholes exist, then why try to go fast? Why not just go instantly? Cover that distance in milliseconds through some kind of spacetime portal.

I don’t think there’s a point to interstellar travel given the time it takes. The time is takes to develop the speed of light tech; the time it takes to reach the speed of light; the time it takes to get to where you’re going; the time it takes to get back; the time that passes on your home world during that travel time relative to the traveler compared to that of those on the home world. All prevent, or at least severely hinder any kind of viable interstellar travel from being developed simply because it might just be pointless.

Unless you realize that it’s a ONE WAY trip. You just go and never return. Relative to you you life wouldn’t change much. But back on your home world, hundreds, even thousands of years will have passed.

Unless civilizations figure out spacetime travel and can instantly transport themselves from one star system to another and back without time-dilation, then interstellar travel is only ONE WAY and pointless, except for those on the ship, and only relative to them.

This is frustrating.

This is a problem of interstellar travel (IT) and why IT is probably pointless; because once you have a propulsion technology advanced enough to make travel to the nearest system viable within a human lifetime, the exponential increase in technological advancement is such that it makes IT pointless at the time the faster propulsion is achieved because in the amount of time it takes to travel from point A to point B at that current top speed, ever faster technology will be developed on the home world, thereby making leaving the home world a pointless endeavor because, why not just wait for faster propulsion to be developed and get there sooner; i.e. an astronaut that waits to leave later with better technology will arrive before the first travelers get there via their older technology. Relative to the first astronauts to leave the home world, when they get to the Alpha Centauri another human could be there already having traveled faster with more advanced technology, even though they left after the original astronauts.

I know I’m not wording this well; it’s the concept that’s important. I don’t even know what you call it. Is it a paradox? Or only a problem?

Seems to me it makes sense to wait. Once you have a propulsion system capable of IT within a human lifetime, then why leave your home world at all at that point? Wouldn’t the rate of the advancement of technology make leaving at that point in time pointless?

This assumes, of course, that technology would continue to advance and we would not hit some unknown/undiscovered technological barrier which prevents the propulsion technology from advancing beyond a certain speed; at which point it would make sense to travel using the current technology and not worry about it. Just write it off as scientific study.

I don’t know. I’m not smart enough to figure this out. Why not just wait? Technology will likely advance exponentially, and that will cut the time it takes to travel between systems exponentially. As faster and faster propulsion systems are developed this continues to reduce the time it takes for IT.

It seems more intelligent to try and develop technology that is not propulsive, but teleports instead.

Teleportation has been hypothesized.

But is it possible?