re: Is it impossible to travel to another solar system?

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And again, you'd be incorrect. I highly suggest you read up Kaku's talks on this topic. It is very much doable.

And we have no basic understanding of physics. We can't even explain the duality of photons.

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Mass–energy requirement
If certain quantum inequalities conjectured by Ford and Roman hold,[16] then the energy requirements for some warp drives may be unfeasibly large as well as negative. For example, the energy equivalent of -1064 kg might be required[17] to transport a small spaceship across the Milky Way galaxy—an amount orders of magnitude greater than the estimated mass of the observable universe. Counterarguments to these apparent problems have also been offered.[1]

Chris Van den Broeck of the Catholic University of Louvain in Belgium, in 1999, tried to address the potential issues.[18] By contracting the 3+1-dimensional surface area of the bubble being transported by the drive, while at the same time expanding the three-dimensional volume contained inside, Van den Broeck was able to reduce the total energy needed to transport small atoms to less than three solar masses. Later, by slightly modifying the Van den Broeck metric, Serguei Krasnikov reduced the necessary total amount of negative mass to a few milligrams.[1][13]

In 2012, physicist Harold White and collaborators announced that modifying the geometry of exotic matter could reduce the mass–energy requirements for a macroscopic space ship from the equivalent of the planet Jupiter to that of the Voyager 1 spacecraft (~700 kg)[5] or less,[19] and stated their intent to perform small-scale experiments in constructing warp fields.[5] White proposed changing the shape of the warp bubble from a sphere to a doughnut shape.[20] Furthermore, if the intensity of the space warp can be oscillated over time, the energy required is reduced even more.[5] According to White, a modified Michelson–Morley interferometer could test the idea: one of the legs of the interferometer would appear to be a slightly different length when the test devices were energised.[19]

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Placement of matter
Krasnikov proposed that if tachyonic matter cannot be found or used, then a solution might be to arrange for masses along the path of the vessel to be set in motion in such a way that the required field was produced. But in this case, the Alcubierre drive vessel can only travel routes that, like a railroad, have first been equipped with the necessary infrastructure. The pilot inside the bubble is causally disconnected with its walls and cannot carry out any action outside the bubble: the bubble cannot be used for the first trip to a distant star because the pilot cannot place infrastructure ahead of the bubble while "in transit". For example, travelling to Vega (which is 25 light-years from the Earth) requires arranging everything so that the bubble moving toward Vega with a superluminal velocity would appear; such arrangements will always take more than 25 years.[9]

Coule has argued that schemes, such as the one proposed by Alcubierre, are infeasible because matter placed en route of the intended path of a craft must be placed at superluminal speed—that constructing an Alcubierre drive requires an Alcubierre drive even if the metric that allows it is physically meaningful. Coule further argues that an analogous objection will apply to any proposed method of constructing an Alcubierre drive.

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Survivability inside the bubble
A paper by José Natário published in 2002 argues that crew members could not control, steer or stop the ship because the ship could not send signals to the front of the bubble.[21]

A more recent paper by Carlos Barceló, Stefano Finazzi, and Stefano Liberati uses quantum theory to argue that the Alcubierre drive at faster-than-light velocities is impossible mostly because extremely high temperatures caused by Hawking radiation would destroy anything inside the bubble at superluminal velocities and destabilize the bubble itself; the paper also argues that these problems are absent if the bubble velocity is subluminal, although the drive still requires exotic matter

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Damaging effect on destination
Brendan McMonigal, Geraint F. Lewis, and Philip O'Byrne have argued that when an Alcubierre-driven ship decelerates from superluminal speed, the particles that its bubble has gathered in transit would be released in energetic outbursts akin to a sonic boom shockwave; in the case of forward-facing particles, energetic enough to destroy anything at the destination directly in front of the ship

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Wall thickness
The amount of negative energy required for such a propulsion is not yet known. Pfenning and Allen Everett of Tufts hold that a warp bubble traveling at 10 times light-speed must have a wall thickness of no more than 10-32 meters—close to the limiting Planck length, 1.6 × 10-35 meters. A bubble macroscopically large enough to enclose a ship of 200 meters would require a total amount of exotic matter equal to 10 billion times the mass of the observable universe, and straining the exotic matter to an extremely thin band of 10-32 meters is considered impractical. Similar constraints apply to Krasnikov's superluminal subway. Chris Van den Broeck recently constructed a modification of Alcubierre's model which requires much less exotic matter but places the ship in a curved space-time "bottle" whose neck is about 10-32 meters. So-called cosmic strings, hypothesized in some cosmological theories, involve very large energy densities in long, narrow lines, but[clarification needed] all known physically reasonable cosmic-string models have positive (positive space-time warping effects) energy densities. These results seem to make it rather unlikely that one could construct Alcubierre warp drives using exotic matter generated by quantum effects.

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Rather than exceeding the speed of light within its local frame of reference, a spacecraft would traverse distances by contracting space in front of it and expanding space behind it, resulting in effective faster-than-light travel.

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I love how we cannot have a civilized debate without the little downvote game starting

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and even if we were able to travel at light speed we would not be able to reach another inhabitable planet in anything close to a human lifetime.

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I think this time it's more based on your certainty that the tech is impossible based on opinions you have gathered. More than who you are.

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Those on Earth would, however.

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Which is irrelevant.

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