swansont

Which phenomenon?

One of the issues here is that "pro-life" is not actually pro-life; they chose that name and it plays well, but the same folks largely do not support efforts to help children survive other than being anti-abortion. They generally don't support efforts to reduce abortion e.g. via birth control and sex education. They also don't support some efforts to keep people from dying via other means. As a group they are objectively not pro-life. They are just anti-abortion.

We already have an indication of a what a kinetic weapon will do to the space environment https://en.wikipedia.org/wiki/2007_Chinese_anti-satellite_missile_test The 2007 Chinese ASAT test was the largest creation of space debris in history, with more than 2,000 pieces of trackable size (golf ball size and larger) officially catalogued in the immediate aftermath, and an estimated 150,000 debris particles.[27][28]As of October 2016, a total of 3,438 pieces of debris had been detected, with 571 decayed and 2,867 still in orbit nine years after the incident.[29] The US withdrawal from the ABM treaty paved the way. By doing so, the US signaled its intent to work on a such systems. It was silly to think that nobody would do so. You can argue that nations would do so in secret, but absent testing, there are limits to how well one can proceed.

They are decidedly not.

You are misrepresenting this, though. Cause and effect is a thing, but that means the cause must precede the effect. It doesn't mean you can't study the effect if you don't know the cause, and it doesn't mean that there are no uncaused things. Knowing the cause makes for a more complete model, but models are built in physics without having "a full unlimited knowledge" of what's going on; I think it's safe to say that all models in physics are made without this full unlimited knowledge.

The answer to a specific question like this may not be (and is probably not) available; you'd have to know the evolutionary ancestors to trace a lineage. Have they been preserved e.g. in the fossil record? If not, then your ability to find out has been decreased. That's why asking for details of the evolution of one particular species is often an exploration of a bad faith discussion. The orchid mantis is an extant species, so it took less than ~4 billion years to evolve.

Yes. There’s a lot of things like that in physics. Physics doesn’t describe reality; it describes how nature behaves. So photons may not be real, but nature behaves as if they are.

Water boiling is changing phase, but it’s still comprised of water molecules, the number of which remains the same. “photons are not matter there for have no mass” has the reasoning backwards. They have no mass, therefore they are not matter.

Fermions have half-integer spin Baryons are made up of an odd number of quarks. Baryons are fermions. Not all fermions are baryons Writing something down doesn’t make it true. Did you get this somewhere? If so, cite your source. Of course matter (and antimatter) can be created and destroyed. You acknowledge annihilation but insist that matter is conserved…

The classical view is matter has mass and takes up space. A deeper dive shows that it’s anything comprised of fundamental fermions. Bullshit. Back this up.

You are asking what physics says about a situation that is unphysical. Physics has nothing to say about it. No. Please don’t make stuff up and post it. Matter is a description; it has no units.

How do you “take away” the mass? It’s the energy it represents that matters, so it can’t just disappear. If you try and analyze a situation that violates physical law, you can’t get a valid answer.

No they aren’t. Taneda is wrong, and you’ve been provided rebuttals of this. Speed is length/time. Speed of gravity ≠ gravity itself Start a new thread to discuss how the speed of gravity has been determined

No. It’s not pure anything. E^2 = m^2c^4 + p^2c^2 (for a particle at rest, this becomes the familiar E = mc^2) If m = 0, then E = pc You can also find this classically for electromagnetic waves

Unfortunately there are few things so outlandish that you can’t find a credentialed person so say/support it. (there are those with physics PhDs who question relativity, for example, and same for biology and evolution) At best it’s a sloppy description that caters to the lay crowd. But it’s wrong and has no place in a discussion striving to have some rigor. We frown on such piggybacking. If your question is not directed at/replying to the OP, it should be asked in a new thread.

Columbus wasn’t looking for a civilization that he didn’t know existed. AFAIK, neither did the proto Polynesians Remember that the context if this discussion is aliens finding us interesting or not, rather than stumbling across us by accident Where does the idea that I am obligated to respond to anything come from? You should ask for your money back.

Have we gone looking for a particular civilization despite not knowing, and having no evidence, that it’s there?

You haven’t given sufficient detail for me to specify anything. I can’t critique a theory/conjecture/idea that has no detail. You say “generation ship” and I’m asking “how does that work?” You (and/or others) start filling in those details and then I’ll be specific. But asking me to specify when you haven’t is just not a fair bargain. I posted specifics in the other thread, so I’ll thank you to stop pretending I haven’t addressed this

What assumptions are invalid?

If I’ve set the bar low, that’s more of an indictment against those who haven’t responded to explore the new proposed technology

Which affects the path of the light.

No such thing as pure energy. Photons - massless- have energy, and also linear and angular momentum. All three are properties, not substances.

Gravity bends light.

Potato, potahto. How can it be ignorant if you can’t/don’t point to any knowledge that would erase that ignorance? What is this missing information? As exchemist has noted, it’s not there are unknowns, as with Lord Kelvin - you would directly contradict known physics, with no basis for doing so. As with others, you point to “solutions” without any consideration of the details involved. Again, I invite you to do some analysis on the technical solutions you present. Absent that it’s just plots from sci-fi stories.

It’s changes in gravity that one would discuss. Gravitational waves propagate at c, as MigL notes above.