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This is my 1000th post! Time to celebrate, This is a fine moment to open the Islay Single Malt I got for Christmas. Cheers from Ghideon, to all new and old form members!

EM radiation has an electric field. If that’s a high enough amplitude, you can cause field ionization.

Well, massless particles do not accumulate any proper time, since they trace out null geodesics, so for them ds=0. But that’s not strictly a minimum, because all possible paths they can take are null geodesics, so this (I believe) is called an infinum, not an extremum. To get a true minimum (saddle point) I think we would have to go to a region of spacetime in the interior of a mass-energy distribution, rather than vacuum. One can probably set up a relevant scenario there, but even then it’s not trivial. I’d also like to mention that any confusion about maxima and minima can be avoided entirely if one considers not proper time, but rather the action (in the theoretical physics sense) of the system in question. One then applies the principle of least action (of which the principle of extremal ageing is only a special case) - the path that is taken then is always a minimum of the action, both locally and globally.

Are not my opinions of his behavior as valid as his opinion of my behavior? Has he supplied the examples of our bad behavior that we've requested? Frankly I cannot understand your support of this poster He has compared "us" or accused us of: - A standard attitude of “STFU, you stupid, ignorant denier" - That we "routinely sling ad homs, insults , and tell others to STFU" - "insults flying" - "boorish behavior" - That we "tell people to STFU and calling them liars, trolls , and ignorant" - That " anyone not agreeing with the mass is either a troll, is stupid, or is just a liar" - "snakiness and snideness" - "a general attitude than anyone who doesn't agree might possibly be a liar" And these "insults" to us have been repeated multiple times in this thread with no substantiation. Frankly I'm growing tired of his boorish, insulting behavior and wish he would just STFU.

Ops! I did not take time differences into account when posting! Maybe we can have a pint (or two) at my next promotion. My conclusion so far regarding this forum and its members: I'll hang around and keep posting...

I’d like to withdraw that previous post. I have a valid point that it’s hard to avoid affecting the election, and also that this impeachment itself is about cheating in that next election so is inextricably linked, but I think directing that to @Raider5678 was rather strained and frankly not appropriate given what he’s actually here saying. He’s right that gaming this out and making choices purely to benefit oneself in the next upcoming election seems inappropriate (though, inappropriate seems also to be par for the course in today’s senate, so who knows), but anyway... Mea culpa.

As long as it's the other side who's undergoing the fatigue. As soon as it's their turn, suddenly they're no longer so willing to say stuff like that. (This isn't targeted at you specifically MigL. I'm commenting more against the people who keep pushing for this on news networks, facebook, forums, etc. It seems like you just heard the idea and mentioned it) People wonder why the republican voters feel this is a political stunt to influence the election. A part of it is because people keep repeating stuff like this. The purpose of impeachment should NOT be to influence the November election. Two wrongs do not make a right. The idea that the House should have held the impeachment papers for the explicit purpose of making sure the memory is fresh in voters mind is a bad one. It's counter to democracy. It's counter to the original intent of impeachment. By all means. Impeach the person. Is he guilty? It sure looks like it. Should he be removed? I believe so. Should impeachment be executed in a particular way for the purpose of influencing the November election? NO! And spreading ideas like this simply feeds the confirmation bias that Republicans have that this is just a political stunt.

The new picture above contains current, I and magnetic field, B. The wire is not attached to anything. So I guess that the wire will be pushed away from the source of magnetic fields B. The picture does not apply to the lifter in earlier drawings. I do not know what that is, does it affect one's ability to make sense or learn physics?

I don't know the mechanism but if you put a fork in a microwave oven or other metallic or carbonized object with points (not safe!) there is a discharge between two tines/points.

Gravitational waves attributed to the collision of two neutron stars could have been produced by something much stranger.... https://www.scientificamerican.com/article/did-astronomers-just-discover-black-holes-from-the-big-bang/?utm_source=quora&utm_medium=referral Snapshot from the central region of a numerical simulation of two merging neutron stars. It shows the stars stretched out by tidal forces just before their collision. Credit: CoRe/Jena FSU

This was really insightful, though slightly displaced from another similar possibility which has crossed my mind... Namely, he consistently ignores feedback in all of his various threads, keeps repeating invalid points even after getting corrected, keeps failing to support anything with evidence even when asked, then gets called out for trolling. Voila! He gets to point back here and tell us all how blinkered we are and how we’re all far too eager to call innocent well meaning people like him trolls... something which all those other better forums would NEVER do.

Thanks for the feedback! A quick check. Router A seems right. Step 2 gets a second route to B through C but since that is longer (=5) you have correctly rejected it. If a third step would be added the router A would get a route to D through B-C but more expensive (=7) so no changes will be made to A's routing table. Router B Seems OK, as argued above Router C has a typo on step 2, I think (0,A) should be (0,C). Also I think the route to A will not change on step 2. Unless there is some weird algorithm or additional information the router will likely keep (1,A) since that is cheaper than going through B at cost 6. Router D seems a little off: 0 | [ (/,/) (/,/) (/,/) (0,D) ] Seems OK 1 | [ (2,A) (0,B) (1,C) (0,D) ] This step could not contain information about A and B yet, how about this: | [(/,/) (/,/) (1,C) (0,D) ] 2 | [ (2,C) (4,C) (1,C) (0,D) ] (4,C) should likely be (5,C) since D->C->B is 1+4=5 3 | [ (6,C) (3,C) (1,C) (0,D) ] (3,C) should likely be (4,C) since D->C->A->B = 1+1+2=4 Important note: I have tried to stay very basic in the analysis above since the exam task does not provide much information. That means that if this is an exam for a specific implementation for instance a certification for a specific brand or manufacturer there could be other things that the exam expects to be taken into account. Additional, non important stuff: I note that this little example looks very simple but contains enough to be used as a basis for a discussion about a lots of additional questions for the interested. Example: if the routers keep the more expensive path instead of dropping them the routers would have backup paths in case of failure. But if they do, additional algorithms may be required. If A knows B can be reached through C, and C knows B can be reached through A, What happens if B goes off-line? Will a package intended for B bounce back and forth between A and C? Such questions is not likely something a network engineer will care much about on a daily bases in a modern environment. Designing the algorithms, improving them, and studying the math behind it is ongoing. The picture reference above is from a book for a course in distributed computing, 1993 edition. Much of it is obsolete now. I guess that newer sources could be based more on interest since the topic contains so much more nowadays.

scuddyx, So you point out that the Time-Handoff scenario using 3 inertial clocks (A, B, and C) produces the same aging outcome of an instantaneous turnabout (impossible) in the classic twins scenario, assuming (of course) that only the legs of transit common to both scenarios are considered. You therefore imply that acceleration may play no role in the relative aging. It's true that the all inertial Time-Handoff scenario produces the very same relative aging as the Twins scenario of instantaneous turnabout. But what the Time-Handoff scenario does not present, is what the Twin B records "for cosmic clocks in his own spacetime system during his own turnabout". It's there, that acceleration's role in the Twins scenario is explained. A proper acceleration produces a dynamic change in his own sense-of-simultaneity wrt all other cosmic bodies. For any complete description of relativity, the "entire experience" of all observers must be presented. And the more difficult experience to explain is that of he who properly accelerates, because other factors come into play (dynamic change in relative simultaneity) that do not exist in all inertial scenarios. There is always a debate as to whether acceleration plays any role in relative aging, since SR relates the relative measure of space and time on relative speed alone. It may have been pointed out already, however there can be no change in relative speed, without a change in at least one observer's own state of motion (acceleration). For the case of a non-instantaneous turnabout, how can you show that the predictions made by both twins A & B will concur wrt the relative aging outcome? You will find that the extent of aging of any clock is simply the accrual of proper time between the events (in the Twin's case, leave earth event, and return to earth event). Since each observer declares himself the reference for all motion, and passing only thru time, his time accrual is nothing more or less than the length of his own worldline between those 2 events. The events, just come to him as he waits. Because both twins (A & B) exist at both events, a valid relative aging comparison may be made between them. The acrrued duration between the events is dependent on nothing but the length of one's own worldine in spacetime. Best Regards, Celeritas

To my knowledge microwaves do not do something fundamentally different to food than other heat sources. What is more important is the overall setup of the cooking method including temperature, length of heat exposure, presence of solvents into which nutrients can transition into (e.g. boiling or deep frying) and so on. A such, studies have shown that the loss of vitamins during microwaving is fairly similar to other cooking methods and may be superior to those where loss can be attributed to higher extraction efficiency (e.g. steam cooking). Many of the listed components are stable at temperatures much higher than used for regular cooking. There are a few heat labile vitamins, but carbohydrate and protein content generally does not change with most cooking methods. One thing to remember is that larger molecules, such as proteins, are not used as a whole, they have to be degraded to smaller bits and pieces before we can actually take them up (which is done by treatment with various enzymes detergents acids etc. in our digestion system). One reason why microwaved food has a bad rep is because food specifically designed for the microwave are often heavily processed and are made to be palatable just by heating it up. But they are rarely made to provide a balanced diet.

Did somebody say 'aether' ? ( gravitational, this time )

This was discussed recently. Here's a really good video that just came out explaining the situation with entanglement and Bell's theorem. This walks through the scenario described by a link Strange had posted in another thread — what the correlations need to be for a hidden variable system with the detectors at 0º, 120º and 240º, what they are in QM, and in experiment.

On the lighter side...

This is an example of the fallacy of begging the question. And it is wrong. Why not learn some physics, instead of making stuff up? Wrong again. The momentum of a photon has nothing to do with mass. It is given by [math]p = \frac{h}{\lambda}[/math]

Succinctly put. And, as Phi for All said, you need the 4th coordinate (“when”) if you want to successfully meet up with someone there. You can’t get away with omitting any of these, and you can’t replace one with some combination of the others, so they meet the “independent” requirement in Mordred’s definition.