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Stephen Hawking Service: Possibility of Time Travellers 'Can't Be Excluded' (bbc.com)

Organisers of Prof Stephen Hawking's memorial service have seemingly left the door open for time travellers to attend. From a report: Those wishing to honour the theoretical physicist, who died in March aged 76, can apply via a public ballot. Applicants need to give their birth date - which can be any day up to 31 December 2038. Prof Hawking's foundation said the possibility of time travel had not been disproven and could not be excluded. It was London travel blogger IanVisits who noticed that those born from 2019 to 2038 were theoretically permitted to attend the service at Westminster Abbey. He said: "Professor Hawking once threw a party for time travellers, to see if any would turn up if he posted the invite after the party. None did, but it seems perfect that the memorial website allows people born in the future to attend the service. Look out for time travellers at the Abbey."

32 of 199 comments (clear)

  1. Everybody is a time traveller. by OpenSourced · · Score: 5, Insightful

    At the breakneck speed of 60 minutes per hour.

    --
    Rome taught me patience and assiduous application to detail. Virtues which temper the boldness of great, general views.
    1. Re:Everybody is a time traveller. by Anonymous Coward · · Score: 2, Insightful

      Well, so we are interstellar space travelers also, at the breakneck speed of the universe expansion.

      So silly.

    2. Re: Everybody is a time traveller. by arth1 · · Score: 3, Informative

      There is a universal clock. It's the speed of light.

      That is not a clock.
      The speed of light in vacuum is 299,792,458 m/s for all reference frames, but that's a ratio. As distance (m) shortens, time (s) contracts so the ratio remains the same. But time changes.

      If you travel at 99.5% of light speed, you might insist that you travelled one light year in a little over a year, yet someone watching your travel from the sideline might say you travelled ten light years in over ten years. Both of you are correct, because both distance and time changes depending on viewpoint.

  2. Dr. Hawking's final joke... by MrKevvy · · Score: 5, Interesting

    He had quite a sense of humor, and use it to cope with his condition. In 2009 when the threw a Time Traveller's Party and no one attended, he indicated that this was confirmation that time travel was not possible.

    And as far as we can tell, it isn't, to the point of ridiculousness, and our physics is validated and complete enough on this to be almost certain. Time travel introduces unresolvable paradoxes (ie sending a single particle backwards far enough in time would completely change future atmospheric patterns, weather events and thus affect who was born, including those doing the sending) and and would require unfathomable physics to carry out (on the order of constraining the energy of a hydrogen bomb in the volume occupied by a human such that no damage or radiation occurred.)

    Not going to happen. If it ever did, being time travel, it already would have.

    --
    -- Insert witty one-liner here. --
    1. Re:Dr. Hawking's final joke... by 91degrees · · Score: 3, Funny

      Well I would have gone, but I heard it was a bit of a bust. Nobody turned up.

    2. Re:Dr. Hawking's final joke... by TheDarkMaster · · Score: 5, Insightful

      well if I were a time traveler I would never show up at a "party for time travelers". Just think about the problems I would have as soon as I proved to be a time traveler, at minimum I would end up locked in some secret government facility or worse.

      --
      Religion: The greatest weapon of mass destruction of all time
    3. Re:Dr. Hawking's final joke... by LordHighExecutioner · · Score: 2

      The reason why no time traveller attended dr. Hawking's party is because all of them were busy at the simultaneous (in the Einstein-Minkowsly sense) party organized by dr. Fermi.

    4. Re: Dr. Hawking's final joke... by reanjr · · Score: 2

      You don't need quantization to solve Zeno's paradox. You just need limits and a basic understanding of how infinity works in algebra.

    5. Re:Dr. Hawking's final joke... by Roger+W+Moore · · Score: 2

      Zeno's Paradox: In theory you can infinitely sub-divide space, in application you can't. Answer: Both time and space are quantized.

      We do not know that. It's certainly plausible but unless you have a working theory of quantum gravity that you have been keeping to yourself, with experimental evidence to back it up, we have literally no idea how space-time works on incredibly small scales.

      You can't violate the Law of Causality no matter how hard you try. It would _instantly_ cause you to cease to exist. Ergo, there is no paradox.

      By its very nature, a time machine violates the law of causality so, if one exists clearly the law of causality can be broken and how to resolve paradoxes is then a legitimate question. If you believe the law of causality to be unbroken then you have to believe that it is impossible to build a time machine.

    6. Re:Dr. Hawking's final joke... by arth1 · · Score: 2

      Going back in time and killing your ancestor, an alleged paradox, isn't. You can't violate the Law of Causality no matter how hard you try. It would _instantly_ cause you to cease to exist. Ergo, there is no paradox.

      You're assuming a single universe and the Copenhagen interpretation. If, as some think, the universe branches at every possible probability because they're all true, there's nothing that logically prevents you from going back in time to kill your grandfather without violating the law of causality, because there will be countless universe branches where you didn't.

    7. Re: Dr. Hawking's final joke... by lgw · · Score: 2

      You've completely misunderstood Zeno's paradox. You've merely stated one of his premises. The question at hand was whether an infinite count of events can be packed into a finite time. The answer is still unclear.

      --
      Socialism: a lie told by totalitarians and believed by fools.
    8. Re:Dr. Hawking's final joke... by arth1 · · Score: 2

      Where is the mass of these other universes?

      Your question does not make sense.
      It's like thinking that the Schroedinger's cat box would have twice the mass because there would be one instance with a live cat and one with a dead cat. That's the case for neither the Copenhagen nor the Everett interpretation.

    9. Re: Dr. Hawking's final joke... by sexconker · · Score: 2

      It does not.

      SUM[i = -1, -inf] 9*(10^i) would be represented in decimal notation by 0.999... or similar.
      That infinite series has a LIMIT of 1. It will NEVER reach one. It is NOT EQUAL to 1. Understanding the difference is fundamental to understanding calculus.

      1/3 has can be represented in decimal notation by 0.333... or similar. Multiplying that decimal result by 3 will result in 0.999... or similar.
      This is NOT EQUAL to 1. The representation 0.333... is indeterminate. Every single "proof" attempting to show that 0.999... is equal to 1 is abusing the fact that the infinite decimal representation is indeterminate.

      If you think 0.999... is equal to 1, what do you think 999... is? Infinity? 1000... ?
      The ellipsis or bar notation represents a repeating series (of digits or terms). For digits, that series may represent a rational number (such as 1/3), but you cannot know that from the ellipsis or bar representation alone.

    10. Re: Dr. Hawking's final joke... by samkass · · Score: 2

      Nope. It equals 1.

      --
      E pluribus unum
    11. Re: Dr. Hawking's final joke... by UnknownSoldier · · Score: 2

      > It is NOT EQUAL to 1.

      *facepalm*

      False.

      You are confusing presentation and representation.

      Proof:

      1/3 = 0.3333... (By Definition)
       
      3*1/3 = 3*0.333... (Multiply both sides by 3x)
       
      1 = 0.999... (Simply)
       
      QED.

      Q. Why?
      Q. The same way there are TWO different way to present 1/3 (integer fraction) and 0.333 (repeating decimal) which represent the SAME value there are ALSO two different way to present 1 and 0.999.... which represent the SAME value.

      1/3 IS EQUAL to 0.333...
      1 IS EQUAL to 0.999...

      It may appear counter-intuitive but rules of Math are consistent. It appears you failed Calculus.

  3. Seems more like an inside joke to me.. by toonces33 · · Score: 4, Interesting

    2038 is when a 32-bit time_t overflows.

    Or maybe the software they wrote for the application process is just buggy. Wouldn't be the first time that ever happened.

    1. Re:Seems more like an inside joke to me.. by complete+loony · · Score: 3, Informative

      Yeah, but that's the 19th of January. Maybe if you attempted to enter a date after that, it would revert to 1970....

      --
      09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
  4. Re:2038? by Anonymous Coward · · Score: 5, Funny

    That is when the world is destroyed by the paradoxes caused by the time traveling device :(

    Those of us here are trying to undo the damage.

  5. Re:If it were possible to time travel by Sique · · Score: 3, Insightful

    If it were possible to time travel then surely someone would have gone back in time and killed everyone trying to kill Muhammad. Since Islam exists, time travel clearly has been achieved.

    --
    .sig: Sique *sigh*
  6. Re:But when by ACalcutt · · Score: 5, Funny

    Colonel Sandurz: Try here. Stop.
    Dark Helmet: What the hell am I looking at? When does this happen in the movie?
    Colonel Sandurz: Now. You're looking at now, sir. Everything that happens now, is happening now.
    Dark Helmet: What happened to then?
    Colonel Sandurz: We passed then.
    Dark Helmet: When?
    Colonel Sandurz: Just now. We're at now now.
    Dark Helmet: Go back to then.
    Colonel Sandurz: When?
    Dark Helmet: Now.
    Colonel Sandurz: Now?
    Dark Helmet: Now.
    Colonel Sandurz: I can't.
    Dark Helmet: Why?
    Colonel Sandurz: We missed it.
    Dark Helmet: When?
    Colonel Sandurz: Just now.
    Dark Helmet: When will then be now?
    Colonel Sandurz: Soon.
    Dark Helmet: How soon?

  7. Possibility of werewolves and vampires... by DeplorableCodeMonkey · · Score: 4, Insightful

    If someone went back in time and changed history, you wouldn't even know it. It's pretty much an impossible to falsify argument. So yeah, it could be true, but then Big Foot could be real along with werewolves, vampires, the Loch Ness Monster, etc. Or how about those sightings of pterodactyls in Papua New Guinea? I mean FFS, if you're going to seriously entertain the time traveler hypothesis, knowing it probably can't be falsified, you can't dismiss things like cryptids either.

    1. Re:Possibility of werewolves and vampires... by shess · · Score: 2

      If someone went back in time and changed history, you wouldn't even know it. It's pretty much an impossible to falsify argument. So yeah, it could be true, but then Big Foot could be real along with werewolves, vampires, the Loch Ness Monster, etc. Or how about those sightings of pterodactyls in Papua New Guinea? I mean FFS, if you're going to seriously entertain the time traveler hypothesis, knowing it probably can't be falsified, you can't dismiss things like cryptids either.

      So you're saying that Nessie was a time traveler? OMG! It explains so much!

  8. Re:Not so complicated by CSMoran · · Score: 4, Funny

    he indicated that this was confirmation that time travel was not possible.

    All that would prove is that observable time travelers didn't come to the party.

    FTFY

    --
    Every end has half a stick.
  9. Re:Can't be excluded by dcollins117 · · Score: 2

    Jesus exists. He's the Mexican fellow that mows my lawn.

  10. Re:Can't be excluded by jawtheshark · · Score: 5, Funny
    A physicist walks into a bar and he orders a beer and turns to the stool next to him and offers it a beer. He finishes his drink and then leaves.

    The next day he returns to the bar, orders a beer, and offers a beer to the stool next to him before finishing his drink and leaving.

    This continues on for a week before the bartender finally asks, " Why in the world do you keep offering that stool a beer?"

    The physicist replies " The laws of physics dictate that there is a slight possibility that at some point the matter above this stool could reform into a beautiful woman, who would then accept the drink."

    The bartender is puzzled for a second before replying " The bar is full of beautiful women. Why not see if they will accept your drink?"

    The physicist quickly laughs before saying " Yeah, but what are the odds of that happening?"

    --
    Ahhh...the great dumpster continuum. Many a free computer will be found there. -- sowth (748135)
  11. Re:2038? by NicknameUnavailable · · Score: 5, Funny

    Why the year 2038?

    They want someone with a primitive enough time machine they can reverse engineer after beating the time traveler to death for it.

  12. Re:pseudo science by sdinfoserv · · Score: 2

    sorry, remember Hitchen's razor: "What can be asserted without evidence can be dismissed without evidence".

  13. Maybe we are just not very interesting by raxtich · · Score: 2

    It's a bit selfish to think a time traveler would even be interested in visiting this exact period in history. What if time travel is discovered 250,000 years from now? Our little blip in that amount of accumulated history might simply be too boring and insignificant to be bothered with.

  14. Re:But when by yodleboy · · Score: 2

    Whatever... My wife didn't make coffee this morning. Now I can't watch radar. Time to play with my dolls.

  15. Re:Can't be excluded by crunchygranola · · Score: 2, Informative

    Any documentation comes from 2nd century, and is very obviously tainted -- either comes from Christians themselves or is a copy of their works. If a preacher leading a popular movement of anything of the scale postulated in the Bible happened, it would be mentioned in secular sources, which have quite detailed records of those times. Yet, any such mentions are conspicuously absent.

    Convincing forgery is tricky to do. Most would be scribe-forgers altering documents they copy to insert things they would like to be there rarely, if ever, sophisticated at who do construct forged passages that would state out from sophisticated textual analysis (consideration of context and textual flow, writing style, word choice, etc.). So modern scholars have a pretty good handle on when passages in ancient texts by one author are altered by insertions of others.

    We have Antiquities of the Jews written by the Jewish historian Josephus about 60 years after the death of Jesus, i.e. written in the First (not Second) Century. There are two passages in this that refer to Jesus that do appear and seem to be originally authentic references from Josephus's hand. They have been altered by Christian scribes to make them more affirmative of Christian claims, but do not appear to be wholesale fabrications inserted later. On the bare question of Jesus's existence the mere fact that any mentions would appear in Josephus's writing supports the historical existence of Jesus.

    This reference meets the demands you make for there to be external surviving references of Jesus's existence. So they are "conspicuously absent" only if you ignore the references that do indeed exist.

    Also, you have a very exaggerated sense for how detailed and thorough the surviving records about the First Century Roman Empire really are, and accounts of happenings in the provinces are nearly non-existent. We did not have a single contemporary piece of evidence of the existence of Pontius Pilate who ruled Judea for 10 years under his name appeared on an inscription found in 1963. Before that the only evidence of his existence were Christian literature and three mentions in non-Christian sources (Josephus was one). There many important Roman documents from that era we know of that have been entirely lost. One example: the last Testament of Augustus Caesar, we did not have a single copy of until fragments of it inscribed on plaques were found in Turkey about 100 years ago.

    On the other hand, there was a lot of religious kooks (this particular thing hasn't changed...), thus it's possible the story has some basis in truth, but has been mangled beyond recognition.

    So, it's like that old Russian joke: "Did you hear that in Moscow they give Volga cars for free?" "Sure, they do, you just got three details wrong. First, not in Moscow but in Leningrad. Second, not Volga cars but Zavmash bikes. Third, they don't give but take away.". Thus, Jesus might indeed have existed, save for some little details...

    All this is absolutely true. We do not have any reliable accounts of really anything about Jesus and in keeping with what one expects from oral accounts, the later things were written down the more extravagant and fanciful (or imaginative) they become. But if we restrict the question to the most basic one - whether there was such a person as Jesus - then we have pretty good evident that it is yes.

    The earliest evidence is best, and that would be the authentic letters of Paul (there are fake ones in the New Testament also) which were written within 20 years of the death of Jesus by a man who had become an adherent within 10 years of his death, and knew several people who had followed Jesus and knew Jesus personally including his brother James (who is also mentioned in Josephus). This documentation at least to existence is as good or better than most people we know of from ancient times who who were not leading members of society or else authors themselves. It is t

    --
    Second class citizen of the New Gilded Age
  16. Re:Can't be excluded by Dragonslicer · · Score: 2

    "Christus", a common biblical term that means "anointed one" -- which required far less chutzpah to claim than "messiah"

    "Anointed one" is exactly what the Hebrew mashiach means.

  17. Re: Can't be excluded by phantomfive · · Score: 2

    A more respectful explanation follows:

    In the 1800s it became popular to question the authenticity of ancient historical characters, naturally the Bible was a prime target, but also people like Bodhidarma, or King Ashoka seemed to legendary to be real (and of course, there are many legends about him, so it seemed natural to consider him as unreal as the great flood). Over time however, a lot of the bible turned out to be real. We found external corroboration of many events. For example, there was a war mentioned in the bible where Assyria put Jerusalem to siege, and then the Lord cursed the Assyrian soldiers with sickness, so they left. Eventually a stone pillar was found commemorating that event, but from the point of view of the king of Assyria, who said he had won the battle (the pillar is now on view to the public at the Oriental Museum at the University of Chicago.....I highly recommend visiting it, and the library which has the biggest multi-volume dictionary you will ever see). Later we found an account from the Greek point of view, which said the Assyrians lost and left because mice invaded their camp. Now, which of these stories is true, that is still a historical mystery, but after the 600BC-900BC range, the record gets more and more reliable. Hezekiah's tunnel has been found.

    So what we see around the world, as more evidence has been collected, is that the weight of evidence suggests that most of these people actually were real, that the legends accreted around a core historical event. As another example, not long ago, there were questions of whether Pontius Pilate was a real person or not, since there was no mention of him in contemporary historical records. Since that time, of course, we've found the Pilate stone.

    There was clearly a movement centered around Jesus Christ in Jerusalem. Based on the evidence that shows how it spread to the East and the West and the South, dating the start of the movement to the fourth decade AD seems reasonable. There is also no reason to believe that it wasn't centered around an actual person. That kind of thing happens fairly often.

    A more interesting question is, "Why did Christianity spread so quickly? What was it that seemed so convincing to the Romans and others who heard it?" I don't really have an answer for that.

    --
    "First they came for the slanderers and i said nothing."