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Responding to you is like drinking too much. Afterwards I'm always saying to myself "you should know better by now, it's always the same hangover".

Gravity doesn't bend spacetime; gravity is bent spacetime. Matter tells spacetime how much too bend. Conversely, spacetime tells matter how to move i.e. its trajectory. 'Fabric' is just a metaphor and not to be taken literally. I think the term originates from the 'heavy ball on a trampoline' idea of bent spacetime, which the fabric represents. It only shows two dimensions; when there's actually 4. It's a very crude idea, not really representing the facts but just gives a glimpse of the concept. 'Spacetime' is actually a 4 dimensional map of the gravitational distribution in a space...it's a mathematical construct. It allows people to plot mass- energy values in time and space on co-ordinates in the spacetime map and see how they change under different scenarios... amongst other things. As you should see, spacetime is not a 'thing' but a way of describing how things behave and interact in space. That behaviour is what we call 'gravity'.

Hey folks, i am an S1 student in Scotland ( it should be 7th grade for the usa ). I've been asked to write a 6 pages essay about General Relativity and it's implications. First, i looked some documentaries on Youtube to understand better how space is connected to time and how both are not absolute as newton described. I think i understood what Albert is trying to say pretty good now. What i don't get is how is it possible that gravity bends space-time, is it the matter that bends it ? or the relation of the mass and the space-time, like in the classic view of gravity ? or does spacetime alone "do the job"?. One last thing i don't really understand in General Relativity is that gravity "seems not to exist", like it is not something defined as a force or a photon. So does gravity exist in Einstein ideas? (Also, but this is for my curiosity: why is it called "the fabric" of space-time ?) Excuse me for the many questions, but i find this theory really really hard to understand even if physics is my favourite subject right now. See you, Ryan.

My 3 year old is capable of screaming with his eyes wide open dripping with tears while drooling and dripping snot and jumping up & down and hitting a kitchen strainer on the wall - all at the same time, multitasking at its finest.

It’s off-topic, so I’ll address this amd move on. It’s the answer provided by respondents when asked: ‘Do you approve or disapprove of the way Donald Trump is handling his job as President?’ The answer choices are: Strongly Approve; Somewhat Approve; Somewhat Disapprove; Strongly Disapprove, Not Sure. 88% of republicans surveyed answered that they approve of Trump, 61% STRONGLY approve. This trend is steady for 2+ years and consistent (if anything, only strengthening) regardless of who conducts the poll. Now, back to the Omar topic...

Lemma, please. Theorem is a bit grand.

It's not that simple. For one thing, there is such thing as a maximum theoretical speed that a spaceship could reach using a given propulsion method. The limits are the practical ones due to how much fuel per kg of rocket mass you need to reach a given speed with any given propulsion method. This is a function of the exhaust velocity your propulsion method generates. Modern day chemical rockets generate exhaust velocities in the order of 4.5 km/sec. There is an equation for determining final velocity with a given fuel/ rocket mass ratio and exhaust speed. It is known as the "rocket equation." Vf = Ve ln (MR) where ve is the exhaust ratio, ln means the natural log and MR is the mass ratio (fully fueled rocket mass/ empty rocket mass) Your 35,000 km/hr = ~9.7 km/s By rearranging the rocket equation, we can work out what mass ratio we would need to reach it with a modern chemical rocket. it works out to a mass ratio of ~8.6 , or 7.6 kg of fuel for every kg of rocket. In the late ''60s and early '70s, NASA worked on developing a fission-based rocket that used a fission reactor to generate its propulsion(NERVA). It could achieve exhaust velocities of ~ 8.1 km/sec. Thus NERVA, with the same mass ratio could reach 17.4 km/sec or just twice that of a chemical rocket. While this does not seem like much of an improvement, it would have made a manned Mars mission practical. Congress however, lost interest in manned space exploration and cut funding to the project. Even with further development, this type of fission reactor rocket design wouldn't have improved its performance that much to make even a dent in the speed of light. A newer approach is the fission fragmentation rocket, which actually uses the daughter products of the fission reaction as the exhaust medium. (NERVA just used the reactor to heat a different working fluid) Theoretically, a Fission fragmentation rocket could achieve exhaust velocities in the order of 3% of the speed of light. With the same 8.6 mass ratio, this gets you up to ~6.5% of c. not bad, but consider the fact that this means that your rocket has to carry 7.6 kg of fissionable material per ever kg of rocket. And the mass of that rocket would have to take into account all the shielding for this, the superstructure to support it, and a means of keeping your fissionable material from prematurely undergoing fission. (anything thing more than critical mass too closely packed will go BOOM, or at the very least generate enough energy to cripple your ship.) This drives the amount of the rocket that is used for useful payload down even further. It gets worse if you plan to slow down. Accelerating to 6.5 c and then decelerating back down to 0 requires you to carry 73 kg of fissionable material per kg of ship. The problem is that you are making linear extrapolations in instances where they don't apply.

For a start, she did what she did, knowing that the law would prevent her becoming stateless. The child was entitled to care under the NHS. She tried to make that happen. If someone has children, and those children subsequently get killed by a drunk driver is it the parents' fault or the fault of the law breaker? Should nobody in any war zone ever have children? Should nobody ever have children because they may end up in a refugee camp?

I don't follow John... "But the really silly idea is that her action several years before the child was born counts as endangering the child" Actions have consequences. Sometimes there is a delay in the consequences. I might choose to, and am responsible for, getting drunk. If I then drive, and hit a pedestrian several hours later, I am still responsible for having gotten previously drunk. If I build an unsafe house, and several years later, it collapses and kills a child, am I not responsible for being negligent and endangering that child ? I am the one who would have endangered the child, not society. The fact that her actions put her child in a disadvantaged situation is no reason to absolve her guilt by making society feel sorry for her, as Dimreepr seems to be suggesting. ( and if I have that wrong dimreepr, perhaps you can stop with the one-liners, and elaborate )

Schrödinger would probably say "yes and no"

You may be able to fool people who haven't studied science at all, but what if the girls actually know quantum mechanics? You should talk about things you know well.

Brevity and sarcasm. No wonder no-one knows WTF you're talking about half the time.

John Cuthber: "Bring them back and take them to court" According to Dimreepr, 'very coherent'. Me: "I say let them come back, have a trial, and jail them for any crimes" According to Dimreepr, 'the definition of prejudice'. All because my 'subtext is pretty clear'. I think you'd better look up the definition of 'prejudice', Dim. ( you can't blame this on stuck keys on your keyboard )

Your right I'm wasting time talking to you. You have nothing worth learning. Yeah once you start pushing killing people as a solution I'm done.

There's nothing inevitable about life. The first living cell was a true miracle. A miracle that included two very complex ingredients and one amazing ability: RNA, the mitochondrion and the ability to split into two identical entities. It baffles me to just think about it. Many theists think this is a sign of divine intervention, but it really is just crazy crazy luck!