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:: john titor, time traveller from 2036 ::I've spent the last couple of days reading a very interesting website, dedicated to the writings (posted in various newsgroups and on discussion forums) of a John Titor, self-proclaimed time traveller from the year 2036. It has been a very entertaining read, to say the least. Some of you may already have read my article on quantum theory, so you'll know that I have a very strong feeling that travel through time is impossible. Now what Mr Titor says, very convincingly, is that he has a machine that creates a dual-singularity using the Kerr theory of spinning black holes, to distort the gravity field enough to force a hole in the fabric of space-time and travel to a parallel world. He also claims that there is only a 1% divergence of "worldlines" between his reality and the one to which he is travelling, for every sixty years travelled. It's a cute idea. Judging by the date on which his postings began, I personally think this is one really clever and bored science geek who in 1999 saw the whole Y2K thing being taken out of proportion, and noticed a little-known fact: that although the UNIX computer operating system is quite impervious to the Y2K bug that we were so scared of, in 2038 it will reset to zero or overflow, because the time is stored in units of a second, in a 32-bit buffer. A 32 bit maximum value is 4294967296. That's the number of seconds from midnight on 1 January 1970 (the default start date for UNIX), to some time in the mid to late 2030s. So he built up this incredible story (which is why he has to be really clever) about how he travelled from 2036 to 1975 to retrieve the original IBM computer that could interpret and debug old UNIX code. He then went forward 25 years or so to "our" time, for personal reasons: he wanted to spend time with his family. Cool, that's really noble and of course he keeps maintaining that he doesn't want to sell anything or convince people, but just to warn us that we are the masters of our own destruction, and that the beginning of the third world war is in 2015. We should love our neighbour, try and eat healthy food, and take our power back from centralised government (in his case, the USA). He also had to be clever to come onto the scene around the end of 1999 and 2000, and then just disappear. That makes his story all the more believable. His basis in quantum science is quite convincing too, with how his machine (photos supplied!) works. Of course, I just have one question: he arrived with this machine, which, if "very heavy", weighs about 500kg I would estimate, and looks quite large, in the back of a 1967 Chevrolet. His "return trip" requires a 4-wheel-drive because the strong suspension needs to support the weight of the machine. Then his "mission" is to get an IBM 5100, "one the first portable computers made" to do the UNIX Fandango outlined above. But later when asked how big the 5100 is, he says "I would say it's about 20" long, 10" high and 30" long". Apart from the bad use of "long" and other typos throughout his postings, if you have this machine with you, and it was your mission to find one, wouldn't you know exactly how big it is? IBM's website has all you need to know about this machine after all ;-). And then my firm favourite: this massive gravitational distortion would probably wipe the memory from the computer. Aw heck, am I spoiling it for you? Okay, so maybe I am looking for ways to catch him out, but this is the kind of person who seems to get a kick out of this sort of thing. I personally think he's a really bored but really clever guy who decided to play a prank. If I'm wrong, I'll recant in 2008. Is that a deal? UPDATE: A nuclear physicist has his say on Titor's claims. [Reproduced without permission. Taken from here.] Well, I'm not really an expert in differential geometry or general relativity, although I'm pretty competent in E&M and special relativity, including the "grown up" forms (group theory and arbitrary boosts and rotations via generators, not just kiddie-physics Lorentz transformations). However, I'd listen to Kaku, if nobody else, reason being some of "Titor"'s time-travel "facts" sound suspiciously like they came straight from Kaku's "Hyperspace", right down to the "who couldn't love strings" discussion. What, Kaku's book is STILL popular reading in 2036? I thoroughly enjoyed it myself, but don't see it surviving until then any more than anybody goes around reading "1-2-3 Infinity" any more. In my previous replies, I really haven't gotten started on Titor's physics -- or his engineering, which is even more egregious. Just this one last time, I will waste a few hours on this by pointing out only a few of the problems. Most serious physicists would probably not bother to waste the time -- you are just lucky I'm not a serious physicist;-) For example, he asserts that his black holes are "the size of an electron" in several places. Say what? An electron is an elementary particle. Elementary particles in physics have no structure -- they are not composite particle bound together with some additional force and hence possessed of a spectral structure. Contrast the electron with the atom (made up of nucleus and electrons; we ARE part of the structure inherent to this system:-). With the nucleus (neutrons and protons, glued with nuclear force, plenty of shell structure:-). With the proton and the neutron (elementary quarks glued with gluons, and yes, there is structure in the form of an SU(3) particle zoo). In all these cases the particles have a "size" consisting of the physical extent of the composite particle wavefunction. An electron or quark is NOT made up (so far as we can tell) of smaller particles glued together. As far as we can tell, with very high energy collisions, they have no physical extent and are >>truly pointlike entities<<. In fact, we EXPECT elementary particles to be pointlike entities, as if they are not pointlike (and if they are charged) we have to figure out what ADDITIONAL force binds all the charge together -- the particle suddenly has a rather large energy associated with its binding. So why say his BH's are the "size of an electron" when there ain't any such thing? Why not say they are "1.7 fermi in diameter" or "the size of a proton" (same order of magnitude, and this is a number that actually exists at least to some approximation). Or just give us the mass -- 10^12 kg, for example. Perhaps because there are some PROBLEMS with that mass, hmmm. There is actually a lot of interesting physics associated with the notion of e.g. electron size. Without boring you with details, there are lovely papers by Dirac, McManus and others concerning radiation reaction, preacceleration, electron size/shape in the classical regime. However, the most amusing result of all of this in the current context is that there IS one (classical) sense in which an electron can be assigned a "size" (and another in a quantum sense, but that is clearly not what he means here as the BH would be much too large to be believable, not that this one IS believable). If one assumes that the electron is a ball of uniform charge, and that the self-energy of all of this charge (bound together with some mythical charge-glue for which there isn't a shred of evidence to the best of my knowledge) is equal to the mass energy, then one gets (ignoring scalar factors of order unity and using "latex" to do ascii algebra, hopefully fairly clearly): \frac{ k e^2} {a} = m_e c^2 which can be solved for a, the classical electron radius: a = \frac{k e^2}{m_e c^2} \approx 3 fm which is not at all coincidentally the same order as the size of the proton or the nucleus of your choice, which DOES confine a net charge of order e with a stronger attractive force but (consequently) has a much larger mass. The Schwarzchild radius for the electron mass is determined from a very similar computation (again neglecting scalar factors order unity) \frac{ G m_e^2} {r_s} = m_e c^2 or r_s = \frac{G m_e^2}{m_e c^2} = \frac{G m_e}{c^2} which is number so tiny as to be meaningless (order 10^-57 meters, smaller than the Planck length and hence it IS meaningless). An amusing computation: Suppose r_s = 1 fm (somewhat smaller than "an electron"). Then m_BH = r_s*c^2/G, right? Plug 'n' chug. On my calculator, 10^-15 * 9x10^16/6.67x10^-11 \approx 10^12 kg. Let's see, that would be, um, a billion metric tons, the mass of a cube of water 1000 meters to the side (as 1000^3 = 10^9 and water conveniently masses a metric ton, 10^3 kg per cubic meter. How come nobody in your group actually did these simple computations? His suitcase contains TWO of these? He carried this suitcase on a 67 Chevy? Man, they must put a hell of a suspension in those babies... Maybe he meant some other "radius of the electron". Alas that I don't know of any, as the electron doesn't have a radius in the first place and even the classical radius above is thus a fairly meaningless artifact. Still, let's suppose that he (a lay person and self-confessed physics idiot) was "confused" and that he meant that the BH's in question were around 10^-24 meters in radius, which is what I get for BH's that mass >>1<< metric ton. We'll use this number below just for the hell of it, since I vaguely recall hemming and hawing by him on the list that suggested that this is the order of magnitude of the size of his BH's. Ha. Next, Titor claims to shoot electrons into his BH to keep up its mass and do all sorts of other things. Oh my sweet Jesus. If you "shoot electrons into a BH", this has the unfortunate side effect of making the ball more and more negatively charged. This has all sorts of interesting (classical) consequences: a) It becomes harder to shoot each additional charge in. It is easy to think "Oh my, it is a black hole and hence gravity MUST be the strongest force present", but this is not only not the case it isn't even CLOSE. Compare ke^2 \approx 10^-28 to GM_b m_e \approx 10^-29 and one sees that within a factor order ten they are the SAME, with electrostatic repulsion likely somewhat higher, and this is assuming, BTW, that the BH mass is 10^12 kg and not 1000 kg. b) Wait! Doesn't that mean that if I shoot one electron in (charging the black hole to -e) that the SECOND electron I shoot into a BH of mass around 10^12 kg is precisely unbound at the black hole radius? So that the black hole may be black for a lot of things, but not electrons? It does. For a black hole to remain bound, the NET FORCE on its components has to create accelerations of order c^2/r_s. Two electrons inside radius a have a repulsive energy (NOT attractive) on the same order as the gravitational binding energy of the entire black hole of the same radius to the same electron. Shooting the second electron into the black hole has a significant chance of knocking the first electron OUT of the black hole (as it becomes unbound) and REDUCING its mass. Or worse. c) Wait again, don't we have to think about quantum mechanics somewhere in here? We do indeed. Even in quantum mechanics the "classical electron radius" is an important number. It is the separation point where two electrons possess enough energy to think seriously about engaging in pair production (scattering electron-positron pairs out of the vaccuum), as they have enough energy to do so, if they have some mass around to use to conserve this and that in the process. In fact, another way of viewing the process classically described in b) is that the second electron gets close to the charged black hole, creates a virtual electron-positron pair while scattering off of it, the positron falls in (attracted by that negative charge AND gravity) where it annihilates an electron in the BH. The two electrons -- the one you shot in and the leftover from pair production -- scatter to infinity and "escape". The black hole itself has more internal kinetic energy (is "hotter"), is less massive, and less stable. IIRC the c) process roughly describes one of Hawking's instabilities, except that he envisions it occurring continuously near the event horizon of small black holes. Any charge imbalance or field imbalance in the electromagnetic force would be nearly instantly neutralized out of the vaccuum at the expense of the BH mass, and even when neutral vaccuum polarization makes decay a steady process. Titor shrugged off Hawking, which he could likely get away with since Hawking is likely too smart to waste his time on this sort of nonsense. If only I were as smart myself...:-) One could go on and on, so I will. We argue above that a BH this size cannot stably be charged (or be stabilized by shooting charged particles into it). Can it have a magnetic moment? Not without a charge and a spin and it cannot have a charge (although I'm almost surprised that Titor didn't assert that his BH contained magnetic monopoles, given all his other tall tales:-). Without a charge or magnetic moment, how do we hold on to it? How do we ENGINEER confinement, even in 2036? See below. quote:> > (Darby's Question): Is there any chance that you can identify the attached jpg? It was > > posted by Titor as a cutaway schematic of his gadget. It appears to > > me to be a vacuum tube based piece of 1960's technology. It was > > suggested to me that it's a pre-internet Arpanet server - but I > > haven't a clue. I sent a copy to UC Santa Barbara to see if they > > can ID it. So far, no luck. Naw, I have no idea what it is -- maybe a klystron unit of some sort for a radar at a guess -- but who cares? This schematic is ridiculous as a BH confinement/manipulation mechanism. Let's start by addressing the question of how we hold onto a black hole that we cannot stick a significant charge or magnetic moment on. Or even one where we can. We don't. Not ONLY do we have to create the damn thing, we have to keep it from falling into Earth's welcoming gravitational well. Clearly, if it masses 10^12 kg, we don't. Period. Ever. I don't care if you are an advanced society that has been around evolving brain for a million years LONGER than humans -- if you start playing with billion-metric-ton black holes near the surface of your planet you are only here for a visit. This is E.E. "Doc" Smith level (e.g. crap) science fiction. Now, if they mass LESS than a metric ton, I don't know why one would bother making them at all, and as noted above this is sort of the number I recall from some fraction of the online discussion, so let's pretend that the BH's are 10^3 kg each and that Titor knows just about as much about the radius of the electron as the history major he claims to be might know. We now have TWO of these pups, each weighing a metric ton, inside of the little chassis below (the size of an oversized suitcase, again from list discussion, at any rate small enough to fit into a pickup truck)? Hmmm. A suitcase that weighs half as much as my Ford Excursion. Hmmm, my Excursion supports its not inconsiderable weight on big, heavy, steel girders. Even my wimpy Ford Contour (which weighs just about as much as this suitcase and its two black holes) uses quite a bit of steel in its construction, and one would really hate to run over a toe with its far more lightly loaded steel belted radial tires. We thus have TWO very serious engineering problems that immediately come to mind. Well, actually more than two, more like thirty or forty or fifty. However, one is keeping the black hole containers from ripping through the bottom of the suitcase itself. Think of the BH containers as being leedle support posts, cross sectional area of a few centimeters squared each, HOLDING UP A FORD CONTOUR. Hmmm, think we need a little more than four little reinforced corners on the box that look sort of like thingies you'd find on the corners of loudspeakers or a suitcase or something else with cardboard sides. And wait, where are the four inch I-beams in the flooring? Where are the grappling eyes on the side (or are humans supposed to lift this thing in and out by HAND?). And this thing was riding in the back of a small pickup truck? Hmmm, not so sure that a SMALL pickup truck could support my Contour as well and not blow out its tires and wreck its suspension, especially a pickup truck that was 70 years old and hard to get parts for. Then there is the even more interesting question: Fine, perhaps they have new materials. Maybe the case has synthetic diamond struts in the bottom, laced into a steel cementation so that one cm of thickness is enough to support a metric ton without any sort of localized bracing or structural forms, spread out over may 100 cm^2. EVEN SO, INSIDE of those little BH container are the BH's themselves. They have to be held, far from any contact with matter, by means of raw E&M forces (unless we're going to suggest new physics, and new physics here would be indefensible I assure you). The mere thought of this has me ROTFL. Seriously. I >>teach<< graduate E&M, and I assure you that the problem of magnetic confinement of thermonuclear plasmas is child's play compared to the problem of confining an object 10^-25 meters across with a metric ton of mass against the Earth's gravitational field, the presumed motion of the long-suffering Chevy pickup truck (gawd, accelerations in arbitrary directions!) and so forth. You see, all the fields involved have to satisfy the laplace equation, and this means that it is almost impossible to create an even weakly attractive region capable of suspending wimpy things like atoms that is STABLE in both a vertical direction and its transverse plane. Try suspending the equivalent of a small car not on the head of a pin, not on an atom, not on a classical ELECTRON, but on an area that aspires to be a mathematical point. Ho, excuse me, I have to wipe my eyes again. Really, a delicious picture. I'd sooner believe in the time travel part. And wait, where the HELL is the hardware for accomplishing this fu**in' miracle? Oh, yeah, those leedle balls. Hey mon, we don't need no stinkin' massive magnetic coils, no gigavolt capacitors, no bus bars the thickness of your wrist. No mon, we got room temperature superconductors, we got new magnetic materials mon, we got monopoles. We can stabilize the BH, mon, and move it around and make it bounce in waves. Hawking? Who is this Hawking mon? Sure, it stable against pair-production-mediated decay. So what if its Schwarzchild radius is WAY WAY smaller than the radius where vaccuum polarization electron pair production begins to be significant and there is enough energy in the gravity well to knock particles out of the vaccuum. It just doesn't happen. But by damn, we still got old-fashioned BNC-style wiring connectors mon, labelled 11. We still got klystrons and big, heavy power switches. And we don't need no stinkin' radiation protection mon -- the fact that we have to shoot about eleventy-zillion electrons at very high energy in an intense electron beam to get ONE ELECTRON to impact on a highly repulsive sphere with a radius of ~10^-24 meters (without creating a shower of secondary particles that cause the BH to DECAY) means nothing, mon. We definitely don't need no bending magnets, no quadrupolar lenses, no accelerator. Hell mon, we can put a gigavolt accelerator inside of a coffee pot now mon -- it's 2036 and we're very tribal now -- and run it with an ordinary eco-approved household battery! Although we don't have to, the suitcase comes with its own fusion generatory mon...it could run a small city if only we could plug it in. Seriously, I could go on and on and on. I haven't even gotten to the raw thermodynamics of it all. That suitcase would require a small lake to cool in operation, for example. And then the culture capable of these miracles of technology that indicate total mastery of materials science, quantum mechanics, gravity, superconductors, a society that has in its possession a star drive (for the goddamn thing would clearly work as such as easily as a "time machine" -- arbitrary translation in four space is arbitrary translation in four space and they have to play all sorts of games to NOT go off into space FTL) then is sending somebody back to our time to get an IBM 5100, a piece of **** computer that is an embarrassment to IBM to this day, because it is somehow capable of some translation chore that appears to be beyond them and is related to the Unix non-problem of a 4 byte unsigned int counter for its current time? This is so clearly a joke that I still cannot believe anybody at all fell for it. It's not even a good joke (believe me, I programmed briefly on the 5100 and I know:-). What, did all the programmers in the world suffer brain damage in the war? Physics got really popular and they could no longer get anybody to learn to program? Computers do all the programming now and programming in C or perl is a lost art? Computers have come to life and are on strike for better working conditions so they are reduced to finding and bringing "back" an IBM 5100 (out of ALL THE COMPUTERS THAT WERE EVER BUILT) in preference to just bringing back a goddamn programming reference for the language(s) they need to translate and building a translator with e.g. perl on a 2036 teraflop PDA? Let me be very, very clear on this. I know that there is a tendency to want to suspend disbelief on things like this. Heck, it is a nifty story, kind of science fiction thing, Orson Welles War of the Worlds internet style. It's "fun" to pretend to believe and kick this sort of thing around, but: WHO COULD POSSIBLY TAKE THIS SERIOUSLY? Screw the physics -- although I personally am by no means convinced that physics even >>permits<< the kind of singularity free time travel they (for this was surely a consortium of jokers) propose. The ENGINEERING is ludicrous. The COMPUTATION is ludicrous (where are the goddam computers in the suitcase? Where is the programming and control interface? Are we supposed to believe that this box has one knob and a switch as a control interface? Where are all the wires?). And as I explained in a reply to somebody else, the entire multiverse story totally ignores the problems of chaos, conservation laws, thermodynamic balance and oh, so much more -- the mere EXISTENCE of a multiverse has consequences in terms of detailed balance and entropy flow in the universe we occupy, and time travel creates a HUGE phase space for global entropy to increase in. You'd never get home again, not without a theory that permitted you to very precisely steer. You'd never get close. Period. I personally have never liked time travel stories (although I've read plenty of them) because they are so difficult to disentangle on the basis of chaos alone (as explored in at least one memorable story, where a single butterfly was killed in a visit to the Jurassic or the like, and upon return the entire Universe was totally different -- as it would be if a single ATOM were displaced a single ATOMIC RADIUS, let alone a butterfly). I do somewhat enjoy multiverse stories, and have even written (but not yet published) one. In my opinion, this isn't even a good multiverse story. Somebody is going to come forth one day and publish a whole book on how they made fun of the entire Internet with a bad story, a sad reflection on the gullability of our culture. And before you ask, yes, y'all can feel free to republish any or all of my replies on your lists, as long as you don't ask me to join them and keep my time-wasting interface to a minimum of a couple or three people. The sooner this matter is really put to rest, the sooner we can all return to leading useful and productive lives DOING SOMETHING ELSE:-) Pardon me while I blow my nose and dry my eyes. There. I feel much better now. Now let's leave it alone, shall we? rgb -- Robert G. Brown Department of Physics Duke University Copyright © 05/12/2003 - 05/09/2005 Randolph Potter Back to previous page | Writing Page
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