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Annabelle05 Just wondering how many of our beliefs and "knowledge" will have changed after another thousand years of scientific learning.
Our knowledge has increased in the past 50 years, more the entire previous 950 years.
Over the next 50 years how much will our knowledge grow? Not really clear we know how much, but it will seem what we now know, trivial.
Are we alone in the universe? Possibly, but we will not likely be able to find out, based on our existing knowledge of the laws of Physics.
We continue to "find" exoplanets that might be conducive to carbon-based life continues to grow. We base it on the following:
- An atmosphere rich in oxygen, nitrogen, and water vapor.
- The planet's temperature should allow for liquid water.
- A magnetic field is essential to protect the planet from harmful stellar radiation.
- Plate tectonics may play a role in stabilizing the climate and recycling essential chemicals.
- Neighborhood. Other planets in the neighborhood, form a "protective" zone, protecting with their gravitational "deflection", the planet from celestial bodies capable of smashing in, and destroying what life developed.
The closest exoplanet identified as potentially habitable (meeting the above conditions) is Proxima Centauri b. It Orbits Proxima Centauri, and is 4.2 light-years away from us.
If a civilization had developed on it, that's about as advanced as ours, and they could travel at half light speed, accounting for time dilation, by the time they reach us, 4.85 years would have elapsed. Not really do-able if their technology is equal with ours.
Assuming our fastest probe, the Parker Solar Probe (700,000 km/h), it would take more than 6,500 years to reach earth from Proxima Centauri b.
The faster we approach the speed of light, the bigger time dilution. If a vessel is traveling near the speed of light for 4.2 years or so, by the time you reach earth, 4.2 years would have elapsed for earthlings, but you would have only aged 1.7 months or so. If you return to your planet, by the time you arrive, you would have aged 3.5 months or so, but the people who were left behind, would have aged more than 9 years or so.
Perhaps, in 1,000 years, we would develop a better understanding, and techniques to nullify the effects of time dilation, or a better understanding of quantum entanglement, and instead of being there, we (or some aliens), would be able to instantly "observe" or "experience", regardless of distance.
But for now, this is probably why we don't have aliens running around, doing anal probes.
