MigL

Elaborating on what Strange said, there are different kinds of measurements. And these are reflected in the types of fields we have. A 'gauge' measurement/field like electromagnetic potential is not 'absolute', I.E. it has no zero point. If you are a bird sitting on a 1000 Volt line, and you measure the next line over at 1010 Volts, you will only measure 10 Volts and not get shocked if you touch it.

I don't know, Stringy... Does that make the problem appear bigger than it actually is ? Or does it make it appear smaller ? ( why does any one need so many guns ??? )

I still don't see a relation, because at no time or place ( except at the possible singularity ) does the gravitational field become non-linear. There is no abrupt change in the way the gravitational field acts at the event horizon, or with increased gravitational 'intensity'. Or do we have differing definitions of the Schwinger limit ? Edited for clarification.

On the contrary , while your posted Shamhosrt link does mention what I previously mentioned about non-linearity and photon-photon scattering, the only mention on, on page 9, about variability of the speed of light is one experimental case, in air ( which I could imagine happening ), but subsequent experiments have failed to comfirm, and the last paragraph in that section clearly states... " Not long after the publication of his work [1] they have checked his assertion in other experiments with higher precision and found no indication for any intensity dependence of the speed of light hereby ruling out any noticeable self-interaction of a light beam with itself (F. Lippich, University of Prague, Austria: [2]; H. Ebert (University of Erlangen, Germany " Edit: @ Giovanni

Just read Giovanni's new link. Isn't that basically the accepted explanation for polar jets from a BH ?

I couldn't get to the link either, but I now know what color underwear Kim Kardashian is wearing today... IIRC the Schwinger limit is where the EM field is strong enough so that interactions are not 'linear' anymore, such that photon-photon interactions are possible because of intermediary electron-positron virtual particle creation. Virtual particles are a requirement of quantum field theory, and as such are present right up to the event horizon of a BH ( most likely inside also but very hard to get evidence ). The fact that an extremely steep gravitational potential could separate virtual particles, allowing one to escape and become real, while the other 'evaporates' the BH seems a no-brainer, and is, in fact, a simplistic explanation of Hawking radiation. But I don't see a relation to the Schwinger limit.

Very interesting article, Strange. Thanks.

Length is frame dependent. Energy is frame dependent.

Whether the premise is true or not, that by helping we are creating a larger problem, the alternative, to stand by and watch people die of hunger/thirst/disease, isn't something I would be proud of as a human being.

Truth be told, I never had much use for philosophy or philosophers, but I have managed to learn a few things on this forum. Eise managed to teach me the purpose of philosophy and earned a great deal of my respect. He knows his physics as well as philosophy. You don't post nearly as much, Gees, but I do agree with a lot of your ideas, including the above list, but maybe not so much the severity of the problems. YDon't be discouraged, your opinions are appreciated, and the rest of us may actually learn something. Even in your thread 'Powerful men, Beautiful women and Sex', I agreed with a lot of your opinions, But I do understand your frustration, and you're right, it seems to happen much more in the 'opinion' oriented fora like politics and religion. Recently two well respected members, Zapatos and Arete, earned down-votes for their opinions about gun ownership, because others disagreed with their opinions and 'ganged up' on them. I would think, Hyper, that the reason we have so many members who think alike is because the ones who have different opinions are made to feel unwelcome, and eventually leave. And maybe not always, but sometimes it is our loss.

If you were falling through the event horizon with a 1 m long stick, you would measure it to be exactly 1 m.

I can't believe that D Trump's idiotic proposal has been discussed for four pages. Only someone like the current president would think that, in a country where the problem is too many guns and their easy accessibility, the solution is MORE guns. Schools need to be gun-free zones. Guns and kids don't mix. Kids need to be taught their problems cannot be solved with violence. Nor are their problems so great these days, as to cause all the teenage angst.

This all reminds me of Newton's pail and Mach's principle... If you take a pail half full of water and spin it, you have various effects that arise because of that rotation, such as the water 'rising' along the edges. Now take that same pail and spin the universe around it. Does the water still rise along the edge ? Ernest Mach proposed that it did, and that this 'attraction' from the far-flung masses of the universe were responsible for inertia.

I'll be more blunt than that. Any useful physical relationship, where one variable is a function of another ( or more variables ), needs to be dimensionally consistent. That is what R. C. Shukla taught me in 4th year at Brock University. I've never doubted him.

Check out the little spat between Itoero and Dimreepr in the Status Update section for an example of the use of neg repping to win an argument, or punish your opponent for having a differing viewpoint. Not taking sides, but that is one good reason for getting rid of down-voting.

That 'equation' you posted Studiot is only true for one specific circumstance. It is not necessarily true for any temperature or pressure, and therefore incomplete. It is equivalent to saying New York= Niagara Falls + 8 hrs. Which is only true if by car. It is +45 mi if by plane, or +3 days if walking. I.E. a totally useless statement, unless other parameters are specified. Dimensional analysis as I understand it, is a tool, used to make sure you haven't slipped up and made two unequal things equivalent. The Force=rate of change of momentum, can be simplified to Force=mass*acceleration, which can have both sides in equivalent units. And that is true always. I.E.that is effectively, a 'check' of the relationship.

The only dimensional analysis I've ever done consists of verifying an equation such that units on either side of the equal sign are equivalent. That is my understanding of dimensional analysis. If there is another, proper meaning, as you understand it, please elaborate. ( so we don't go on for several pages as to whether its 'visible' or not )

I would have to say yes. Although sometimes, there is a 'cheat' involved which uses the constant of proportionality to make the dimensional analysis equivalent. As an example, does dimensional analysis determine the units of G, the gravitational constant, or, are the units, m^3*kg^-1*s^-2 , somehow measured, thereby verifying the dimensional analysis of Newton's Gravitational equation ?

When the Shah was still in power in the 70s, Iran was ( still is ) a rich country, and a favorite of the US. They were the only other country allowed to buy the Grumman F-14, the most advanced weapon system available at the time, able to track up to twenty targets, and achieve firing solutions for up to six, independent, beyond visual range targets with its loadout of Phoenix missiles. That would be equivalent to any country buying the F-22 today. It will not happen. But you know, even with the embargo after the revolution, and further embargos following ( for nuclear ambitions ), quite a few of those F-14, as well as F-5e, which have even been built as modified local versions, are still flying today. They built their own spares, and have an aerospace industry. I find it strange that they would source their airliners from the US. Why not Airbus with RR engines ? Or Ilyushins with Aviadvigatel engines ? Aeroflots planes aren't falling out of the sky. Or are they just trying to garner sympathy, by blaming their poor upkeep on the US led sanctions ?

I could be mistaken, but I don't think I've ever down-voted any post. If I don't agree with a post, I would rather explain why, so I, personally, have no use for them. I do occasionally like some posts, mostly for the humor content. I get the impression that sometimes, down-votes are used as the argument, and to 'gang up' on people with unpopular opinions.

I've gotta ask... Ten oz has posted numbers such as 52 million people who own guns in the US, and net sales of the gun and ammo industries of over 50 billion dollars. That makes an average expenditure of approx. $1000 per person, per year on guns and ammo purchases. Either those sales include military and foreign sales ( i.e. the numbers are over-inflated ), or America has a bigger problem than I thought. My opinion, for what its worth. What Zap, Moony and Raider should be saying... " I will give up any guns, over and above the numbers, and the type, that society deems acceptable ( so that none are too dangerous or fall into the wrong hands ) I will abide by rules and regulations with respect to purchase, ownership, carrying and discharging of firearms as society deems acceptable. I accept that mental conditions, such as youth, depression, senility, etc. may affect my rights to purchase or own ANY gun. And that previous actions on my part, such as a criminal record of violence, will also affect these rights." I wouldn't dare presume to tell you guys what to do, and I'm certainly not calling for an outright ban.

Expansion is NOT a velocity. Because of expansion, light emitted by objects 13 Bill yrs ago, has actually travelled over 30 Bill Light yrs.

To be fair, Zapatos, Moontanman and Raider are the last people that need convincing of the need for more effective gun control regulations. They are some of the most sensible people I've had the pleasure of knowing ( on this forum ). All three of them have stated they wish to see more effective regulations, and thanks RangerX, for being unusually understanding of Zapatos' position ( I may have misjudged you also ) and providing details of the Canadian standards. Hounding them until they pledge to give up their guns, is counterproductive, and one of the obstacles to getting an effective discourse about gun control

Marxism is so passe. Anarchism is all the rage these days. Try to keep up !

These 'negotiations' are nuts. We dance around like there's some give and take, so that gun owners can be happy and gun control advocates can be happy. Most of us on this forum can spot the correlation a mile away... People are dying because of easily accessible guns. Your hobby, whether hunting or target shooting, is causing unnecessary deaths. And the fact that you need a gun to protect yourself from all the others who have guns, says something about the magnitude of the problem. I like you guys, Zap, Moony and Raider, and have a lot of respect for you, but what would it take, how many deaths, how many schoolchildren killings, what size body count, before you can say " No more" ?