PLato said,"Look to the perfection of the heavens for truth," while Aristotle said "look around you at what is, if you would know the truth" To Remember: Eskesthai
Time has no independent existence apart from the order of events by which we measure it. — Albert Einstein
Currently with the new book written by Lee Smolin about Time, to me, it is a fundamental question about what arises, and, on how we use time to measure. Also for me, to ask what relevance time means, as an emergent product for any beginning.
LEE SMOLIN- Physicist, Perimeter Institute; Author, The Trouble With Physics
Thinking In Time Versus Thinking Outside Of Time
One very old and pervasive habit
of thought is to imagine that the true answer to whatever question we
are wondering about lies out there in some eternal domain of
"timeless truths." The aim of re-search is then to "discover" the
answer or solution in that already existing timeless domain. For
example, physicists often speak as if the final theory of everything
already exists in a vast timeless Platonic space of mathematical
objects. This is thinking outside of time. See: WHAT SCIENTIFIC CONCEPT WOULD IMPROVE EVERYBODY'S COGNITIVE TOOLKIT?
Darwinian evolutionary biology is the prototype for thinking in time
because at its heart is the realization that natural processes
developing in time can lead to the creation of genuinely novel
structures. Even novel laws can emerge when the structures to which they
apply come to exist. Evolutionary dynamics has no need of abstract and
vast spaces like all the possible viable animals, DNA sequences, sets of
proteins, or biological laws. Exaptations are too unpredictable and too
dependent on the whole suite of living creatures to be analyzed and
coded into properties of DNA sequences. Better, as Stuart Kauffman
proposes, to think of evolutionary dynamics as the exploration, in time,
by the biosphere, of the adjacent possible. See:Thinking In Time Versus Thinking Outside Of Time
While we then become cognoscente of the rules around which parameters have meaning in relation to Time, it was also important to understand that the idea of cross pollination of the sciences recognizes what is brought to the table.
"It is very good that Stu Kauffman and Lee
are making this serious attempt to save a notion of time, since I think
the issue of timelessness is central to the unification of general
relativity with quantum mechanics. The notion of time capsules is
still certainly only a conjecture. However, as Lee admits, it has
proven very hard to show that the idea is definitely wrong. Moreover,
the history of physics has shown that it is often worth taking
disconcerting ideas seriously, and I think timelessness is such a one.
At the moment, I do not find Lee and Stu's arguments for time threaten
my position too strongly."- Julian Barbour
In regard to The Adjacent Possible I was well aware of the implication and parameters around such thinking to realize that even while applying the trade, Stuart, was traveling new ground. His thinking is encouraging the flexibility that I am talking about with regard the restrictions one places on them self. I encourage this kind of thinking so as to bolster the lull in scientific advancement to stimulate and foster the idealization of creativity that I think has become stagnate while moving from one point in the measure to the next. Why Murray Gell-Mann's move and his expertise is understood in context of new approaches. Simplicity and complexity.
Return to Home, Safety seeking, In my mind, Continually speaking
Out of the sky, Eyes Earthbound, Stalagmite in open cavern, Fertile lands all around.
The era of design, Like a Justice Hall, Women in bonnets, Mennonite clothes,
In the Town of Williams, Some time ago, In the late eighteen hundreds, Scenery I know.
by Platohagel
Before I begin I just wanted to say I am deeply connected to the science today and what I am displaying now may not sit well with scientists. Those who discount subjectivity as a part of our existence not tried and tested. This subjective existence\experience is real and very individual. How could you discount this from a point of a view of a scientist. I thought they might say, but yes, lived with responsibility and in a true validated sense?
So it was in this sense that one could consider the exercise that follows as a science fiction possibility that raises the questions about time and the relationship of the probability distribution of a possible future and the lived past. The present, in becoming, and in this case, I wanted to look at the past.
The question is that we know that the world of subjective influences and experiences are deeply personal in that they become the life you have live. We work all day and we work all night in the virtual realities.You discover the Intent in the Actualized?
This distinction if not understood within the parameters of the subject entertained it would have lacked the understanding that our virtual reality within the confines of the parameters as being explicit in what we create would have been missed. I can talk about such a park and you might believe the context of such an example if I were to tell you that I was able to remember that at a very young age.
Can an individual experience the actualized past as if viewing a place in our history as part of that history. These questions had crossed my mind over 35 years ago as I explored the dream world. I tried to keep as much of this in poetic form dreaming as I was experiencing it. So I thought it would be nice to write it down in that form.
Now there are many reasons why this area of subjectivity was of interest to me. It was in that what I believed, that not only our footprints left an image in the sand, but our impressions of our life was in the footprints.
Two section variable capacitor, used in superhet receiver
Technically such excursions would have been of interest if I could track the ability by some means. So it was not beyond me to think that a tuning could take place by some individuals in helping to reconstruct the past by going back in time. Not only by Carbon dating. But possibly by some other technical means as well in terms of a super heterodyne solution.
Now I am sure the idea of a fireman and a radio might be trigger in your mind. Aurora flickering in the sky and a son who goes to work on his Dad's radio? You will find many references to time travel in this blog because of this idea I have had for a long time about our the ability each of has to visit the historical past as an Intent in the Actualized.
Frequency is a 2000 science-fiction film that contains elements of the time travel, thriller and alternate history film genres.
So the idea for me here was about creating a device that could tune into the past? Why then, is it we are not capable in consciousness as a virtual reality?
The Super Hero Versions
Miracles StudiosThrone Plates
To
activate Thorne plates, the distance between each plate must be less
than the width of an atom. The resulting wormhole will be equally small,
so getting in and out might be difficult. To widen the portal, some
scientists suggest using a laser to inject immense amounts of negative
energy. In addition, Thorne believes that radiation effects created by
gravitons, or particles of gravity, might fry you as you enter the
wormhole. According to string theory, however, this probably won't
happen, so it's scant reason to cancel your trip.
Miracles StudiosGott Loop
To
take you back one year, the string must weigh about half as much as the
Milky Way galaxy. You'll need a mighty big spaceship to make that
rectangle.
Many scientists believe the big bang that created the
universe left behind cosmic strings - thin, infinitely long filaments of
compressed matter. In 1991, Princeton physicist J. Richard Gott
discovered that two of these structures, arranged in parallel and moving
in opposite directions, would warp space-time to allow travel to the
past. He later reworked the idea to involve a single cosmic-string loop.
A Gott loop can take you back in time but not forward. The guide to
building your own:
Miracles StudiosGott Shell
This is a relatively slow method of time travel, and life inside the shell could become tedious.
In
essence, a Gott shell is a huge concentration of mass. The shell's
sheer density creates a gravitational field that slows down the clock
for anyone enclosed within it. Outside, time rolls along at its familiar
pace, but inside, it creeps. Thus the Gott shell is useful for travel
into the future only. If you're planning a jaunt to the past using a
Gott loop, you might want to bring along a Gott shell for the return
trip. What to do, step by step:
Miracles StudiosVan Stokum Cylinder
The cylinder must be infinitely long, which could add slightly to its cost.
Mass
and energy act on space-time like a rock thrown into a pond: the bigger
the rock, the bigger the ripples. Physicist W. J. van Stockum realized
in 1937 that an immense cylinder spinning at near-light speed will stir
space-time as though it were molasses, pulling it along as the cylinder
turns. Although Van Stockum himself didn't recognize it, anyone orbiting
such a cylinder in the direction of the spin will be caught in the
current and, from the perspective of a distant observer, exceed the
speed of light. The result: Time flows backward. Circle the cylinder in
the other direction with just the right trajectory, and this machine can
take you into the future as well. How it works:
Kerr Ring
The
Kerr ring is a one-way ticket. The black hole's gravity is so great
that, once you step through it, you won't be able to return.
When
Karl Schwarzschild solved Einstein's equations in 1917, he found that
stars can collapse into infinitesimally small points in space - what we
now call black holes. Four decades later, physicist Roy Kerr discovered
that some stars are saved from total collapse and become rotating rings.
Kerr didn't regard these rings as time machines. However, because their
intense gravity distorts space-time, and because they permit large
objects to enter on one side and exit on the other in one piece,
Kerr-type black holes can serve as portals to the past or the future. If
finding one with the proper dimensions is too much trouble, you can
always build one yourself:
Déjà vu (French pronunciation: [deʒa vy] (listen),
literally "already seen") is the experience of feeling sure that one
has already witnessed or experienced a current situation, even though
the exact circumstances of the prior encounter are uncertain and were
perhaps imagined. The term was coined by a Frenchpsychic researcher, Émile Boirac (1851–1917) in his book L'Avenir des sciences psychiques
("The Future of Psychic Sciences"), which expanded upon an essay he
wrote while an undergraduate. The experience of déjà vu is usually
accompanied by a compelling sense of familiarity, and also a sense of
"eeriness", "strangeness", "weirdness", or what Sigmund Freud calls "the uncanny".
The "previous" experience is most frequently attributed to a dream,
although in some cases there is a firm sense that the experience has
genuinely happened in the past.[1]
The psychologist Edward B. Titchener in his book A Textbook of Psychology
(1928), wrote that déjà vu is caused by a person getting a brief
glimpse of an object or situation prior to full conscious perception,
resulting in a false sense of familiarity.[2] The explanation that has mostly been accepted of déjà vu is not that it is an act of "precognition" or "prophecy", but rather that it is an anomaly of memory, giving the false impression that an experience is "being recalled".[3][4]
This explanation is supported by the fact that the sense of
"recollection" at the time is strong in most cases, but that the
circumstances of the "previous" experience (when, where, and how the
earlier experience occurred) are quite uncertain or believed to be
impossible. Likewise, as time passes, subjects can exhibit a strong
recollection of having the "unsettling" experience of déjà vu itself,
but little or no recollection of the specifics of the event(s) or
circumstance(s) they were "remembering" when they had the déjà vu
experience. In particular, this may result from an overlap between the
neurological systems responsible for short-term memory and those responsible for long-term memory
(events which are perceived as being in the past). The events would be
stored into memory before the conscious part of the brain even receives
the information and processes it.[citation needed]
Links with disorders
Early researchers tried to establish a link between déjà vu and serious psychopathology such as schizophrenia, anxiety, and dissociative identity disorder,
and failed to find the experience of some diagnostic value. There does
not seem to be a special association between déjà vu and schizophrenia
or other psychiatric conditions.[5] The strongest pathological association of déjà vu is with temporal lobe epilepsy.[6][7] This correlation has led some researchers to speculate that the experience of déjà vu is possibly a neurological anomaly related to improper electrical discharge in the brain. As most people suffer a mild (i.e. non-pathological) epileptic episode regularly (e.g. a hypnagogic jerk,
the sudden "jolt" that frequently, but not always, occurs just prior to
falling asleep) it is conjectured that a similar (mild) neurological
aberration occurs in the experience of déjà vu, resulting in an
erroneous sensation of memory.
Pharmacology
Certain drugs increase the chances of déjà vu occurring in the user.
Some pharmaceutical drugs, when taken together, have also been
implicated in the cause of déjà vu. Taiminen and Jääskeläinen (2001)[8]
reported the case of an otherwise healthy male who started experiencing
intense and recurrent sensations of déjà vu upon taking the drugs amantadine and phenylpropanolamine
together to relieve flu symptoms. He found the experience so
interesting that he completed the full course of his treatment and
reported it to the psychologists to write up as a case study. Due to the
dopaminergic
action of the drugs and previous findings from electrode stimulation of
the brain (e.g. Bancaud, Brunet-Bourgin, Chauvel, & Halgren, 1994),[9]
Taiminen and Jääskeläinen speculate that déjà vu occurs as a result of
hyperdopaminergic action in the mesial temporal areas of the brain.
Memory-based explanations
The similarity between a déjà-vu-eliciting stimulus and an existing, but different, memory trace may lead to the sensation.[5][10]
Thus, encountering something which evokes the implicit associations of
an experience or sensation that cannot be remembered may lead to déjà
vu. In an effort to experimentally reproduce the sensation, Banister and
Zangwill (1941)[11][12] used hypnosis
to give participants posthypnotic amnesia for material they had already
seen. When this was later re-encountered, the restricted activation
caused thereafter by the posthypnotic amnesia resulted in three of the
10 participants reporting what the authors termed "paramnesias".
Memory-based explanations may lead to the development of a number of
non-invasive experimental methods by which a long sought-after analogue
of déjà vu can be reliably produced that would allow it to be tested
under well-controlled experimental conditions. Cleary[10]
suggests that déjà vu may be a form of familiarity-based recognition
(recognition that is based on a feeling of familiarity with a situation)
and that laboratory methods of probing familiarity-based recognition
hold promise for probing déjà vu in laboratory settings. Another
possible explanation for the phenomenon of déjà vu is the occurrence of "cryptomnesia",
which is where information learned is forgotten but nevertheless stored
in the brain, and similar occurrences invoke the contained knowledge,
leading to a feeling of familiarity because of the situation, event or
emotional/vocal content, known as "déjà vu".
Parapsychology
Some parapsychologists have advocated some unorthodox interpretations of déjà vu. Ian Stevenson and a minority of other researchers have written that some cases of déjà vu might be explained on the basis of reincarnation.[13][14]Anthony Peake has written that déjà vu experiences occur as people are living their lives not for the first time but at least the second.[15]
Jamais vu (from French, meaning "never seen") is a term in psychology
which is used to describe any familiar situation which is not
recognized by the observer.
Often described as the opposite of déjà vu, jamais vu involves a
sense of eeriness and the observer's impression of seeing the situation
for the first time, despite rationally knowing that he or she has been
in the situation before. Jamais vu is more commonly explained as when a
person momentarily does not recognize a word, person, or place that they
already know. Jamais vu is sometimes associated with certain types of aphasia, amnesia, and epilepsy.
Theoretically, as seen below, a jamais vu feeling in a sufferer of a delirious disorder or intoxication could result in a delirious explanation of it, such as in the Capgras delusion, in which the patient takes a person known by him or her for a false double or impostor. If the impostor is himself, the clinical setting would be the same as the one described as depersonalisation, hence jamais vus of oneself or of the very "reality of reality", are termed depersonalisation (or surreality) feelings. Times Online reports (see semantic satiation):
Chris Moulin, of the University of Leeds,
asked 95 volunteers to write out "door" 30 times in 60 seconds. At the
International Conference on Memory in Sydney last week he reported that
68 percent of the volunteers showed symptoms of jamais vu, such as
beginning to doubt that "door" was a real word. Dr. Moulin believes that
a similar brain fatigue underlies a phenomenon observed in some
schizophrenia patients: that a familiar person has been replaced by an
impostor. Dr. Moulin suggests they could be suffering from chronic
jamais vu.[16]
Déjà vu is similar to, but distinct from, the phenomenon called tip of the tongue,
a situation when someone cannot recall a familiar word or name, but
with effort one eventually recalls the elusive memory. In contrast, déjà
vu is a feeling that the present situation has occurred before, but the
details are elusive because the situation never happened before.
Presque vu (from French, meaning "almost seen") is the sensation of being on the brink of an epiphany.
Often very disorienting and distracting, presque vu rarely leads to an
actual breakthrough. Frequently, one experiencing presque vu will say
that they have something "on the tip of my tongue".
Déjà entendu
Déjà entendu, (literally "already heard") is the experience of
feeling sure that one has already heard something, even though the
exact details are uncertain and were perhaps imagined.[17][18]
Reja vu
The feeling something that has happened or is happening will happen
again, possibly in the near future, possibly in the distant future.
In popular culture
Film
Déjà vu provides a plot point in The Matrix, a 1999 science fiction-action film written and directed by Larry and Andy Wachowski. The protagonist, Neo,
glances at a black cat and comments that he has just experienced déjà
vu. Those with a knowledge of 'The Matrix' and its internal workings
state that déjà vu means something within the Matrix was altered from
its prior state and is referred to as a "glitch".
The 2006 science fiction film Déjà Vu
revolves around a US federal law enforcement officer using an
instrument called Snowhite to view the past 4 and a half days of
anywhere in the world (limited radius as permissible by the program) in
order to solve a murder and a terrorist bomb attack on a ferry that was
being boarded by about 500 citizens and military members.
Television
Déjà Vu was the third episode of the second season of Monty Python's Flying Circus, a British comedy program. Michael Palin plays a television host with the problem.[19]
The concept is explored in the episode 119 of Garfield and Friends in the Orson's Farm segment.
The final episode of season 1 of Charmed, called "Déjà Vu All Over Again" sees Phoebe Halliwell reliving the same day over and over again at the hands of a demon named Tempus.[20]
Déjà Vu is also a recurring plot element on Fringe.
In the Season One episode, "The Road Not Taken", Olivia described the
experience of déjà vu to Walter after she briefly experienced an
alternate reality as the result of being a Cortexiphan subject. In the
Season Two episode "White Tulip", Olivia experiences déjà vu while
investigating the apartment of a time traveler who reset the timeline.
Déjà Vu is also a plot element in the "Mystery Episode" of the
television series Supernatural where Sam Winchester wakes up in the same
day as a result of being trapped in a time loop.
^Taiminen,
T.; Jääskeläinen, S. (2001). "Intense and recurrent déjà vu experiences
related to amantadine and phenylpropanolamine in a healthy male". Journal of Clinical Neuroscience8 (5): 460–462. doi:10.1054/jocn.2000.0810. PMID11535020.edit
^Bancaud,
J.; Brunet-Bourgin; Chauvel; Halgren (1994). "Anatomical origin of déjà
vu and vivid 'memories' in human temporal lobe epilepsy". Brain : a journal of neurology117 (1): 71–90. PMID8149215.edit
^ abCleary, Anne M. (2008). "Recognition memory, familiarity and déjà vu experiences". Current Directions in Psychological Science17 (5): 353–357. doi:10.1111/j.1467-8721.2008.00605.x.
^Banister H, Zangwill OL (1941). "Experimentally induced olfactory paramnesia". British Journal of Psychology32: 155–175.
^Banister H, Zangwill OL (1941). "Experimentally induced visual paramnesias". British Journal of Psychology32: 30–51.
^Fisher, J. (1984). The case for reincarnation. New York: Bantam Books.
^Stevenson, I. (1987). Children who remember past lives. Charlottesville, VA: University Press of Virginia.
^Anthony Peake Is There Life After Death? The Extraordinary Science of What Happens When We Die Arcturus Publishing Limited, 2012 ISBN 184837299X
First
came the heterodyne. The principle of "beats" or difference tones
between simultaneous audio pitches was well known since antiquity, but
Reginald Fessenden in 1901 was the first to apply the principle to radio
transmissions [3]. Originally both radio frequencies were to be
transmitted, received with two antennas, and combined in a detector.
Later a local oscillator was substituted for one of the
transmitter-receiver combinations and the heterodyne as we know it was
born. Fessenden himself coined the term, from the Greek heteros (other)
and dynamis (force).Who Invented the Superheterodyne?
Time has no independent existence apart from the order of events by which we measure it. — Albert Einstein
While Event has since past, I hope the lecture itself will remain in public domain. It helps so as to see the context of the discussion provided by this conference with regard to that subject of time.
Since there exists in this four dimensional structure [space-time] no longer any sections which represent "now" objectively, the concepts of happening and becoming are indeed not completely suspended, but yet complicated. It appears therefore more natural to think of physical reality as a four dimensional existence, instead of, as hitherto, the evolution of a three dimensional existence
If man thinks of the totality as constituted of independent fragments, then that is how his mind will tend to operate, but if he can include everything coherently and harmoniously in an overall whole that is undivided, unbroken, and without a border then his mind will tend to move in a similar way, and from this will flow an orderly action within the whole. (David Bohm, Wholeness and the Implicate Order, 1980)
Bar of Lead TungstateSource: A Quantum Diaries Survivor-Calorimeters for High Energy Physics experiments - part 1 April 6, 2008
Calorimeters measure the collective behavior of particles traveling along approximately the same path, and are thus naturally suited for the measurement of jets-Dorigo Tommaso
Life must be understood backwards; but... it must be lived forward. Soren Kierkegaard
The image illustrates the Wayback machine from the Mr. Peabody and Sherman segment of the Rocky and Bullwinkle cartoon. The image supports the article on the subject: Wayback machine. The screen shot was selected to illustrate the nature and size of the Wayback machine (compare to images of UNIVAC or ENIAC machines).
I mean whats sets the whole package off to wonder how such neurons once isolated, as to being components of all the things we learn, then becomes a method by which we now see ? What sets off the spark to think that technologies will be superseded by the efforts by mind, to think that all we have to do is turn the switch off? The technologies no longer work? That this is somehow the fate of a mind who no longer seeks to find meaning, or, is settled to the fate of mundane happenings which replay them-self time and time again.
Boids is an artificial life program, developed by Craig Reynolds in 1986, which simulates the flocking behaviour of birds. His paper on this topic was published in 1987 in the proceedings of the ACMSIGGRAPH conference. The name refers to a "bird-like object", but its pronunciation evokes that of "bird" in a stereotypical New York accent.
As with most artificial life simulations, Boids is an example of emergent behavior; that is, the complexity of Boids arises from the interaction of individual agents (the boids, in this case) adhering to a set of simple rules. The rules applied in the simplest Boids world are as follows:
So, you've built up this vast reservoir of information as neurons, and all time that began from embryonic growth seeks to find them-self distinct to all the functions of the human body. To think we have become who we are today, as a sign of all these possibilities are but the evolution of a pattern played out as an example of the evolution of being manifested through this body? Manifest now, once one expresses through the fingers as an extension of mind, to be built up, as all those things which represent self .
So you step back then, looking as if from outside, looking in, as to wonder what is new being garnered are but piecemeal represents some larger view of the reality of groups, to present an awareness greater then that which is though to exist, as some local issue in it's understanding, is more the societal flock with purpose, unawares of the significance of choices made? How do societies change?
So there is then this reservoir of information, many facets and capabilities of mind to choose those things which are brought together through the journey, all encompassing it's growth, this potential exists as if a flash, like lightning strikes from which are born new neuronal pathways. Perception, is then changed. Many connections in life take place where none were seen before.
The mystery of time travel is explored as we embark on an adventure to reveal if traveling into the future will one day be a reality. Next we examine if traveling into the past will have bizarre consequences. Finally, are scientists on the verge of discovering an Earth-like planet within the next few years?
Clifford gives a heads up, as well some appearances in the production of.
I have always been fascinated by the Time travel scenarios as they have been presented in story form. I do appreciate the subtleties of the proper interpretations as sciences knows it in context of it's proper form.
I just noticed that last week’s episode of The Universe on Time Travel, which I told you about here and here, is available online on their website. Click here to learn more about the ins and outs of it, and I show you how to make one too! Kind of.Clifford of Asymptotia
Black Hole-Powered Jet of Electrons and Sub-Atomic Particles Streams From Center of Galaxy M87
NASA's Hubble Space Telescope Yields Clear View of Optical Jet in Galaxy M87
A NASA Hubble Space Telescope (HST) view of a 4,000 light-year long jet of plasma emanating from the bright nucleus of the giant elliptical galaxy M87. This ultraviolet light image was made with the European Space Agency's Faint Object Camera (FOC), one of two imaging systems aboard HST. This photo is being presented on Thursday, January 16th at the 179th meeting of the American Astronomical Society meeting in Atlanta, Georgia. M87 is a giant elliptical galaxy with an estimated mass of 300 billion suns. Located 52 million light-years away at the heart of the neighboring Virgo cluster of galaxies, M87 is the nearest example of an active galactic nucleus with a bright optical jet. The jet appears as a string of knots within a widening cone extending out from the core of M87. The FOC image reveals unprecedented detail in these knots, resolving some features as small as ten light-years across. According to one theory, the jet is most likely powered by a 3 billion solar mass black hole at the nucleus of M87. Magnetic fields generated within a spinning accretion disk surrounding the black hole, spiral around the edge of the jet. The fields confine the jet to a long narrow tube of hot plasma and charged particles. High speed electrons and protons which are accelerated near the black hole race along the tube at nearly the speed of light. When electrons are caught up in the magnetic field they radiate in a process called synchrotron radiation. The Faint Object Camera image clearly resolves these localized electron acceleration, which seem to trace out the spiral pattern of the otherwise invisible magnetic field lines. A large bright knot located midway along the jet shows where the blue jet disrupts violently and becomes more chaotic. Farther out from the core the jet bends and dissipates as it rams into a wall of gas, invisible but present throughout the galaxy which the jet has plowed in front of itself. HST is ideally suited for studying extragalactic jets. The Telescope's UV sensitivity allows it to clearly separate a jet from the stellar background light of its host galaxy. What's more, the FOC's high angular resolution is comparable to sub arc second resolution achieved by large radio telescope arrays.
Willem Jacob van Stockum (November 20, 1910-June 10, 1944) was a mathematician who made an important contribution to the early development of general relativity.
Van Stockum was born in Hattem in the Netherlands. His father was a mechanically talented officer in the Dutch Navy. After the family (less the father) relocated to Ireland in the late 1920s, Willem studied mathematics at the Trinity College, Dublin, where he earned a gold medal. He went on to earn an M.A. from the University of Toronto and his Ph.D. from University of Edinburgh.
In the mid nineteen thirties, van Stockum became an early enthusiast of the then new theory of gravitation, general relativity. In 1937, he published a paper which contains one of the first exact solutions in general relativity which modeled the gravitational field produced by a configuration of rotating matter, the van Stockum dust, which remains an important example noted for its unusual simplicity. In this paper, van Stockum was apparently the first to notice the possibility of closed timelike curves, one of the strangest and most disconcerting phenomena in general relativity.
A Tipler Cylinder uses a massive and long cylinder spinning around its longitudinal axis. The rotation creates a frame-dragging effect and fields of closed time-like curves traversable in a way to achieve subluminal time travel to the past.
***
We see a pulsar, then, when one of its beams of radiation crosses our line-of-sight. In this way, a pulsar is like a lighthouse. The light from a lighthouse appears to be "pulsing" because it only crosses our line-of-sight once each time it spins. Similarly, a pulsar "pulses" because we see bright flashes every time the star spins.
