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ArcticMyst Security by Avery

Alien Life

Do you think life exists outside of Earth?


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Well these far beyond our technology craft are coming from somewhere.
 





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That was my point in the beginning of this thread. We can't exceed the laws of physics, so even if life exists somewhere else in the universe, we will most likely never know. And Star Trek warp bubbles are a theory that was likely invented to give possibility to science fiction plots and devices. Such theories exist only in the imagination of people. There is no science to back it up.
 
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The theory may yield such a reality, NASA is working hard on proving it now.
 
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That was interesting. In the first sentence Neil deGrasse Tyson called the idea "far-fetched". But, he added that the fact that people are thinking about it shows that people still have the explorer mind set in them. This article is over 2 years old and the photon travelling past the speed of light has still not happened. I'm with Neil on this one. It seems far-fetched to me too.
 

WizardG

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Quote, "We can't exceed the laws of physics".

True enough, but we're still learning what those laws are. The Standard Model, as successful as it is, is not the last word on the subject.
 
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I keep seeing the mindset faster than light travel is impossible due to well known equations preventing mass from even reaching that speed, let alone surpassing it... but, just because we can't see a way to do so, doesn't mean there isn't a way. The universe itself is expanding faster than the speed of light now, including the matter in it, relative to other parts of the universe, once we understand how to move space itself, the universe will become much smaller.
 
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Space is expanding. Mass is not. There have not been any new discoveries since the early 20th century to indicate any of this is possible. Hope springs eternal. :D
 
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Planets with mass are moving apart faster than the speed of light due to the expansion of the universe, is what I meant. The theory of being able to move space faster than the speed of light appears solid to me, whether we will ever do so, or when, tell me that and then where your magic ball is at to give you the information :p
 
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Yes, but how fast? Every 3 million light years of space is moving apart by about 42.6 miles per second. That is a whole lot of space and it is moving away at the ends at very sub light speeds. Now, if you take the farthest points we can see in opposite directions, that is very fast. But, how are you going to make that into a way to make space the size of the solar system expand faster than light speed? It isn't happening. You have to put these things into context.
 
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It's the far, far distances which have an increasing velocity away, the further you get, the faster they are moving away: Is the universe expanding faster than the speed of light? (Intermediate) - Curious About Astronomy? Ask an Astronomer

Regarding the theory of moving space to get somewhere using some kind of space-warp drive very well may be possible, probably need to access zero-point energy first though, the energy demands are so high I don't see how we could get enough energy to do so without it.
 
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The further away two points in the universe are the faster they are moving away from each other. It is actually expansion and not velocity we are talking about here. We measure these speeds by the shift in the light's wavelength at distant points in space. But, it is still expansion and not velocity. The point in space is not moving with a greater velocity because it is farther away from us. Space itself is expanding. And if you take two points 3 million light years apart, they are expanding away from each other at very sub light speeds. But, using the word speed here is not really correct.

If you take a balloon and put some dots all over it, then blow it up, this is an analogy from what is happening in the universe. Nothing in space itself is able to move faster than the speed of light. And it never will. Or, a whole lot of physics that works perfectly well is all wrong.
 
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Yes, understood. Just bringing up that the expansion of space at the far reaches from any one spot can move faster than light, manipulating space somehow to move space quicker than the speed of light may be possible someday and explains how craft ffom other star systems might be able to get here.
 

GSS

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Lets say there was a universe that had a exact planet just like our Earth and went through the same stages of time, weather, minerals, dinasours extinction, etc...
Would you think technical inventions like the wheel, the internal combustion engine, jet engine tech would be basicly the same.
It a very vague and silly question but you know where i'm going:whistle:
 
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Encap

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An interesting historical look at the speed of light quest, courtesy of Cosmos as follows:

"We all know the number one traffic rule of the universe – nothing can travel faster than the speed of light. And that happens to be 299,792.458 kilometers per second. But why is it so?

Before the 1600s most people assumed light moved instantaneously.

Galileo was among the first to think that light traveled at a finite speed.
In 1638 he tried to measure it. He and an assistant perched themselves on distant mountaintops with covered lanterns. The idea was that as soon as Galileo’s assistant saw the flash, he uncovered his lantern. Galileo would then time how long it took to see the return flash. The experiment failed dismally! To succeed, Galileo would have had to register a time difference of microseconds. He had no such time keeping device and his reaction time would be way slower than that. Undaunted, Galileo concluded that light’s movement, “if not instantaneous, is extraordinarily rapid”.

But not long after, in 1676, we got a fair estimate of light’s speed from a young Danish astronomer by the name of Ole Römer. One of the ways sailors at sea checked their clocks was to observe the eclipse of Jupiter by its moon Io. The time for Io to make one complete circuit around Jupiter had been measured at 1.769 days. However there was a minor problem.
Römer observed that the time between eclipses varied slightly depending on the time of year. At times when the Earth was moving away from Jupiter, the time between Io’s eclipses gradually increased; as it moved closer the time decreased. The cumulative effect meant the predicted times could be in error by more than 10 minutes.
Römer realised his observations could be explained by the varying distance between Jupiter and Io, and Earth. The different times for Io’s orbit reflected the different distances light had to travel. It also allowed Römer to estimate the speed of light as 214,000 km/s. Not bad!

The first experimental measurement of the speed of light came 150 years later with Hippolye Fizeau. He came up with an ingenious advance on Galileo’s method. In his experiment, a beam of light was projected onto a rapidly rotating cog-wheel. The teeth of the rotating cog chop the light up into very short pulses. These pulses travelled about 8 kilometres to where Fizeau had positioned a carefully aligned mirror. On the return trip, the reflected light pulse could only reach Fizeau by passing back through one of the gaps in the cog-wheel.
What happened? At slow speeds, the light pulse always got back to Fizeau through the same gap in the cog’s teeth. But as Fizeau turned the wheel faster, at a certain speed the pulse was blocked by the following tooth. Knowing the rotational speed, Fizaeau thus could calculate how long it took for light to travel 16 kilometres – and so how fast the light must be travelling. His remarkable result of 315,000 km/s was within about 5% of our most recent measurements using lasers.

We know that light travels at a finite speed. But why is it finite?

This question gave Albert Einstein pause for thought. If light has a finite speed, what if you strapped a torch to the front of a moving rocket? Wouldn’t the light coming from this torch be traveling faster than the speed of light? Einstein puzzled over this issue with several “Gedankens” (thought experiments) and came up with a crazy solution: the motion of an object must somehow make time slow down. Time was no longer constant and so relativity was born.

Many experiments have carefully tested Einstein’s predictions.
In 1964, Bill Bertozzi at MIT accelerated electrons to a range of speeds. He then measured their kinetic energy and found that as their speeds approached the speed of light, the electrons became heavier and heavier – until the point they became so heavy it was impossible to make them go any faster. The maximum speed he could get the electrons to travel before they became too heavy to accelerate further? The speed of light.
In another crucial test, physicists Joseph Hafele and Richard E. Keating flew synchronized, super-accurate caesium atomic clocks on various trips around the world on commercial airliners. After the journeys, all the moving clocks disagreed with each other and the reference clock back in the lab. Time ran slower for the moving clocks just as Einstein predicted.

By the way, the next time you use your smart phone be aware that the GPS satellites orbiting Earth have to take the slowing of time (time dilation) into account. Disable these relativistic corrections and the modern world would be lost forever." ~ from: https://cosmosmagazine.com/physics/why-can-t-anything-travel-faster-light


 
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