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Posts posted by geordief

  1. 28 minutes ago, swansont said:

    This suggests you don’t know what entanglement is, or what was being proposed. How do you entangle space? What properties would be entangled?

    How would entanglement create spacetime? 

    I looked at the Susskind video.He seems to be saying that adjacent regions of space contain particles (virtual particles,was it?) that are entangled.

    So the property of space being entangled (if I understood the lecture) was its property of containing  entangled particles close to  either side of a line dividing it.(not just at the event horizon  of a BH but generally)


    And I think Susskind did refer to this as "space being entangled"


    I found that extraordinary and I  think perhaps most  physicists may disagree with that (Susskind's caveat) but ,if that is accepted then he goes on to say that that might violate " entanglement monogamy"

  2. 32 minutes ago, ovidiu t said:

    Must be some species preservation mechanisms. Joggling between "past" experiences and "predicting on the go" the present?  

    Not sure what you mean.Our brains have no choice but to extrapolate from past data to create a "virtual present" and a likely future.

    Our brain processes are not instant and that is how we and every entity ,a;live or non-sentient  live.


    It is "freedom within boundaries" .


    As the expression goes ,time is what stops everything happening at the same time.(or words to that effect)


    edit "Time is what prevents everything from happening at once.” John Archibald Wheeler


  3. 15 minutes ago, ovidiu t said:

    a bit off topic: at individual level, the way the consciousness is "awake" and building the reality is already altering the process of understanding the present or it has  something to do with it. I am referring at "time slices" of consciousness every 400 millisecondes.


    The present is the prisoner of the law of synchronicity/simultaneity. To grasp the present, Time would need to be absolute in value. 


    As  the "time slices" of the brain become theoretically smaller (approach zero) the amount of energy required to process data approaches infinity (=impossibility)Our brains can observe  the world  for the very reason that  we cannot do that(grasp the "present")

  4. 12 minutes ago, Time Traveler said:

    In my opinion it is a big problem because the observations who the observer makes is like he observes a cloud who has now form of a mountain  and his conclusion is , there is a mountain  in the cloud

    We all make mistakes and hopefully learn from those mistakes.

    We cannot know everything and have to apply our resources to those things that we can most accurately know and which are likely to be most beneficial or of most consequence.

    If something  is unclear to us we can investigate further and it may become clearer.

  5. 2 hours ago, StringJunky said:

    You routinely make such statements with no context or explanation. Do you get a kick out of being purposely vague? This is my thread. Please stop. Telepathy is not one of my talents.

    On topic: I think the true long term intent of the present administration is clear in the Defence Minister's statement in answer to the US's statement admonishing the settler's current exploitative tactics in the West Bank:


    This Smotrich guy?


    Not the Defence Minister-the Finance Minister and excluded from the War Cabinet  from my cursory knowledge.

  6. 22 minutes ago, swansont said:

    Things that sounds like “that’s simply not done because we’ve never done it” i.e. a very conservative, non-empirical response. Consistent with the description John Cleese gives in “A Fish Called Wanda”

    Wanda, do you have any idea what it's like being English? Being so correct all the time, being so stifled by this dread of, of doing the wrong thing

    Not “don’t do that, it tastes awful” which would be empirical though subjective. Or “do it if it’s to your liking” No, it’s “that’s not the proper way to do it, personal enjoyment be damned”

    Think you are reading too much in to it.


    Myself otoh bought one of Cleese's books *(and I  might buy just one or two books a decade) and was unable to "read into it"  more than the first 10 or so pages ,so earnest  it seemed to me.


    Well my concentration/absorption  levels have dipped the last good few years (I felt the same about Hemingway  who I also thought would be an interesting read)

    * Life and How to Survive It


  7. 59 minutes ago, swansont said:

    I fund it interesting that the pushback I’ve seen on this is that it goes against tradition rather than evaluating whether or not it makes for better tea.

    That is because it is (apparently) only of very incremental interest to the consumer of the beverage whereas the cultural significance of the drinking of the tea is far more  important.

    There is also the humour involved in the Boston Tea Party  where the English and the Americans are free to have a good laugh at each other if they want to.

    You kicked us out of your country using the "tea issue" at  the outset but we are the ones who (in our minds at least) actually know how to use the stuff.

    Any coincidence that the phrase "a storm in a teacup" is still fairly widely used?

    The Japanese also hold tea in high estime(not so sure about other countries)

    Don't see what "pushback" you mean.

    I am sure it may well make a difference in the taste but ,personally speaking I have never added sugar to tomatoes even though it is well known that it makes it taste better and is often recommended in recipes.....

  8. 32 minutes ago, sethoflagos said:

    It does. Been recycling tepid tea that way for years.

    But tea (-making)is a social occasion ,a ritual of sorts I always felt.

    Do you offer up warmed up old tea to your friends and visitors?


  9. 1 minute ago, dimreepr said:

    Oh boy, it's really kicking off over here, all the builder's have vowed to creat a wall to protect their elevenses. 

    I have heard  some of the sugar cubes  imported  via Canada may have been predoped with  a sodium substitute.

  10. 2 hours ago, exchemist said:

    The person behind this is apparently a serious tea drinker who puts milk in her tea a l'anglaise and says Britain is one of the few places where can reliably expect a decent cup of tea. So she's not some wacky Californian vagina-steaming nutcase, apparently. She says a very small amount of salt, not enough to make the tea perceptibly salty in taste, deactivates the taste buds that detect bitterness.

    What I don't quite follow is that if you put milk in your tea (a habit I think we got from India), that too cuts the bitterness from the tannins. So why do we need both? However I might try it this afternoon, just to see if I can detect a difference.

    What is funny about this story is the humorous, faux-panicky statement put out by the US embassy in London, averring that no way was the USA now trying to tell the Brits how to make tea!   

    Be careful not to get culturally  expropriated.Don't put on a checked shirt  and camera for the tasting session.

  11. 27 minutes ago, sethoflagos said:

    Personally I take my tea strong, black and well stewed. The more astringent the better within reason.

    But it seems there are some folks who just can't get enough blandness into their lives. Salting tea sounds to me as doolally as decaf, but whatever floats your .

    Back in the 60's our school teacher told us not to overstew tea because ,after a few days it contains arsenic!

    I already mentioned this school teacher to @TheVat. in a previous,  completely unrelated thread.

    He had been held in a  prisoner of war camp (shot down in a bombing sortie) in Germany  ,which might explain how he came to have such apparently arcane knowledge.

  12. 23 minutes ago, TheVat said:

    In the Vat household, where some are very particular about their brew, it is believed that loose leaves in a steel tea ball (or infuser) are the way to go.  None of that weird bag taste or potential polyester nanoparticles.  And brew times not to exceed five minutes - after that, tannins (the source of bitterness) tend to build up.  Milk or cream is considered an abomination.  As for listening to Yanks on arcane practices like adding salt, you should remember that we once had a famous tea party which resulted in very salty tea...


    I must have gone 60 years without going near a tea bag for various  reasons but have  adapted to the habit as some of the new flavours available in green teas  only come with bags.

    I can't say I notice any taste from them  and I don't know about nano particles -I throw the bags ,along

    with the coffee filters into the "donkey bucket" and have always supposed they are made from something compostable. 

    The coffee filters,especially  are the thing they go after first.


    Otherwise cabbage leaves are popular ,but I don't stand and watch-they never touch the grapefruit halves or ,obviously lemons.


    I seem to remember the French hadn't a clue about making or serving tea and we used to be given a cup of warm water with a tea bag either in or beside the cup when we went into a cafe back then.

    They probably pitied us for needing it in the first place.


    "Britain’s media has reacted with fury and bewilderment after a US scientist claimed the perfect cup of tea is made with a pinch of added salt"



    Apparently a soupçon of salt  takes away the supposed bitterness of the drink of tea.

    I can't see that catching on but then I myself drink  very ,very weak green tea (obviously no milk -also no sugar)

    I was never aware that bitterness was a problem with ordinary  black tea  but perhaps there is to some.

  14. 1 hour ago, MigL said:

    Your notion of acceleration is not totally valid even for classical systems.
    Your 'push'/'pull' analogy only works for contact forces; it does not work in the case of gravity, or electromagnetic forces, where the whole body interacts with the force, not just the contact surface.

    Quantum mechanically things are no different.
    Contact forces, such as the LHC, are treated the same because the EM part of the interaction is small/weak compared to the collision part.

    One slight difference is that, classically, most people use Newtonian mechanics, but any 'advanced' treatments, including Quantum mechanical and Relativistic, use Lagrangian or Hamiltonian mechanics ( energy of the system ), as Swansont alluded to previously..


    Is it possible for two particles to collide without new  sub particles being created ?

    Does "particle dodgems" or "particle pinball" exist in practice?

    Can one particle influence the trajectory of another without the  fireworks? (do their waves just superimpose in a continuous way?)

  15. 1 minute ago, Sensei said:

    Aren't CERN and the LHC examples of accelerators that accelerate quantum particles to near the speed of light?

    New (usually short-lived) particles appear, and other particles are destroyed into smaller components, etc. etc.

    That example occurred to me after I had asked the question.

    So the particles collide and as a result new particles result.

    Do they accelerate away from the region where the "parent" particle was?

    Or do they  travel like  a photon ,either at zero velocity or at c?

    If the latter then they don't accelerate  and the acceleration as in "particle accelerator " is a classical  process.

    28 minutes ago, swansont said:

    What would be a comparable situation?

    That is why I put it in quotes.As "comparable" as possible ,I suppose.

    Are there any situations where a quantum system undergoes anything like what a classical system does when it is subject to accelerating  forces?

    I think you are saying there aren't?


    Is it possible to treat a quantum particle (system?) classically?

    Does that introduce error?

  16. Are there examples of how acceleration is treated in quantum theory?

    If a classical system is accelerated I have a picture of a wave traveling through the system like if you were to pull a string or push a rod.

    What happens in "comparable" situations  when the systems are quantum?

    Does "acceleration" mean anything under those circumstances? 

  17. 10 minutes ago, dimreepr said:

    I have no problem in believing that.

    But in the twin analog, when twin A reaches the age of twin B, they would have the same number of heart beats, doesn't that mean the tick frequency is the same, but that the ticks of twin B were stretched when compaired to twin A?

    In which frame of reference?

  18. A cricket commentary as reported on a facebook account(the late Brian Johnson)


    "Sometimes, unintended humour can be the best. The late Brian Johnson was a star performer when on Test Match Special. He once remarked innocently, ‘the batsman’s Holding, the bowler’s Willey.’ When he realised his statement was hardly appropriate he had a fit of giggles. It still makes me smile. Not what he said, but his reaction to it" 


    There was all this too (gaelic games commentaries of old)

    Legendary witty GAA commentator Mícheál O'Muircheartaigh is an active 93. Thanks to Ferghal McCarthy for these live gems.
    -Sean Óg Ó hAilpín: his father’s from Fermanagh, his mother’s from Fiji. Neither a hurling stronghold.
    -Anthony Lynch, the Cork corner-back, will be the last person to let you down – his people are undertakers.
    -The stopwatch has stopped. It’s up to God and the referee now. The referee is Pat Horan. God is God.
    - Brian Dooher is down injured. And while he is, I’ll tell ye a little story: I was in Times Square in New York last week, and I was missing the Championship back home. So I approached a newsstand and I said, “I suppose ye wouldn’t have The Kerryman, would ye?” To which, the Egyptian behind the counter turned to me and he said, “Do you want the North Kerry edition, or the South Kerry edition?” He had both – so I bought both. And Dooher is back on his feet…
    Colin Corkery on the 45 lets go with the right boot. It's over the bar. This man shouldn’t be playing football. He’s made an almost Lazarus-like recovery from a heart condition. Lazarus was a great man but he couldn’t kick points like Colin Corkery.
    Teddy McCarthy to Mick McCarthy, no relation, Mick McCarthy back to Teddy McCarthy, still no relation.
    I saw a few Sligo people at Mass in Gardiner Street this morning and the omens seem to be good for them. The priest was wearing the same colours as the Sligo jersey! 40 yards out on the Hogan Stand side of the field, Ciarán Whelan goes on a rampage… it’s a goal! So much for religion.
    He grabs the sliothar, he’s on the 50! He’s on the 40! He’s on the 30… he’s on the ground!
    Pat Fox out to the forty and grabs the sliothar. I bought a dog from his father last week. Fox turns and sprints for goal… the dog ran a great race last Tuesday in Limerick… Fox, to the 21, fires a shot – it goes to the left and wide… and the dog lost as well.
    In the first half, they played with the wind. In the second half, they played with the ball.
    1-5 to 0-8… well, from Lapland to the Antarctic, that’s level scores in any man’s language.
    Pat Fox has it on his hurl and is motoring well now, but here comes Joe Rabbitte hot on his tail… I’ve seen it all now, a Rabbitte chasing a Fox around Croke Park.
    Here’s another I recall; " Jimmy Barry Murphy. Jimmy Barry Murphy. One of the ten. The ten who have won All Ireland Hurling and Football Senior Medals. He will be spoken of till the end of time”.
    Teddy looks at the ball, the ball looks at Teddy…
    Mike Houlihan for Limerick. He had his jaw broken by a kick from a bullock two months ago. He’s back now. ‘Twas some bullock that broke Mike Houlihan’s jaw!
  19. 3 hours ago, Markus Hanke said:

    Yes, true - I’ve been neglecting these, to avoid that extra level of complexity.

    This really is kind of tricky to get one’s head around. That’s one of the reasons why spacetime diagrams, like the one Genady has posted, are so useful - you can see immediately whether geodesics intersect or not.

    Looking at it physically ,the light from P's nose recedes from him at c   .He follows ,whilst outside the EH at <c 

    You say he "catches up" with it .Is that because the light from his erstwhile  nose  radiates in all directions and so he "catches up" or "falls into"  that  part of the light that is not receding directly away from him  but with a component back towards him?(which is red shifted?)

    If there was just one photon receding directly along  his "line of site" he wouldn't even see it red shifted?

  20. 19 hours ago, Markus Hanke said:

    The diagram is necessarily correct (it shows a valid solution to the EFE), and I think so is Genady’s interpretation of it.

    The thing is that, at the event horizon, something very unintuitive happens - the physical meaning of the coordinates we use is no longer the way we are accustomed to. Imagine an astronaut in free fall, just as he crosses the horizon - let’s for simplicity’s sake say his feet emit light. Once his feet have crossed the horizon, and always assuming free fall, this light signal is now no longer “below” the eyes, but in their future. Light below the horizon is perfectly free to propagate in all spatial directions, yet it can still never leave the BH, because the singularity is in the future, and the horizon is in the past. It is no longer a question of up, down, above or below, once you’re past the horizon.

    Thus, for the astronaut, the light leaves his feet, and his eyes will necessarily “meet” it, because he’s in free fall. Both age towards the singularity, their relative velocity remains c (so everything is locally Minkowskian), yet their geodesics must intersect, just as the diagram shows. Thus he sees his feet like normal, perhaps slightly redshifted and dimmed. He will otherwise never notice anything special at the horizon. And he can’t, because locally everything must look Minkowskian.

    This is probably the biggest mistake people make when trying to visualise black holes - they think that, past the horizon, the singularity is “down”; but it’s not, it’s in the future. Likewise, the horizon isn’t “up”, but in the past. This is extremely important to understand, or else there’ll be all sorts of misunderstandings.

    It’s the other way around, see also above - light past the horizon remains past the horizon, but the eyes which see that light are falling inwards, and can intersect that light in the future. 

    Very far from understanding this but can I ask ,if the up and down coordinates that apply outside the EH are replaced with future and past inside the EH  what are the future and past coordinates that applied  outside the EH replaced with inside the EH?

    Are there any spatial coordinates that apply inside the EH and  can they be visualized?

    They wouldn't be flattened on the EH itself ,would they? (that's a wild ,desperate guess)

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