Time: Do the past, present, and future exist all at once?
Does time exist? Here's what the debate is all about.
MICHELLE THALLER: Is time real or is it an illusion? Well, time is certainly real but the question is what do we mean by the word time? And it may surprise you that physicists don't have a simple answer for that.
JAMES GLEICK: Physicists argue about and physicists actually have symposia on the subject of is there such a thing as time. And it's also something that has a traditional in philosophy going back about a century. But, I think it's fair to say that in one sense it's a ridiculous idea. How can you say time doesn't exist when we have such a profound experience of it first of all. And second of all we're talking about it constantly. I mean we couldn't get, I can't get through this sentence with out referring to time. I was going to say we couldn't get through the day without discussing time. So, obviously when a physicist questions the existence of time they are trying to say something specialized, something technical.
BILL NYE: Notice that in English we don't have any other word for time except time. It's unique. It's this wild fourth dimension in nature. This is one dimension, this is one dimension, this is one dimension and time is the fourth dimension. And we call it the fourth dimension not just in theoretical physics but in engineering. I worked on four dimensional autopilots so you tell where you want to go and what altitude it is above sea level and then when you want to get there. Like you can't get there at any time.
GLEICK: Einstein or maybe I should say more properly Minkowski, his teacher and contemporary, offers a vision of space-time as a single thing, as a four dimensional block in which the past and the future are just like spatial dimensions. They're just like north and south in the equations of physics. And so you can construct a view of the world in which the future is already there and you can say, and physicists do say something very much like this, that in the fundamental laws of physics there is no distinction between the past and the future. And so if you're playing that game you're essentially saying time as an independent thing doesn't exist. Time is just another dimension like space. Again, that is in obvious conflict with our intuitions about the world. We go through the day acting as though the past is over and the future has not yet happened and it might happen this way or it might happen that way. We could flip a coin and see. We tend to believe in our gut that the future is not fully determined and therefore is different from the past.
DEAN BUONOMANO: If the flow if time, if our subjective sense of the flow of time is an illusion we have this clash between physics and neuroscience because the dominant theory in physics is that we live in the block universe. And I should be clear. There's no consensus. There's no 100 percent agreement. But the standard view in physics is that, and this comes in large part from relativity, that we live in an eternalist universe, in a block universe in which the past, present and future is equally real. So, this raises the question of whether we can trust our brain to tell us that time is flowing.
NYE: In my opinion time is both subjective and objective. What we do in science and engineering and in life, astronomy, is measure time as carefully as we can because it's so important to our everyday world. You go to plant crops you want to know when to plant them. You want to know when to harvest them. If you want to have a global positioning system that enables you to determine which side of the street you're on, from your phone you need to take into account both the traditional passage of time that you might be familiar with watching a clock here on the Earth's surface, and the passage of time as it's affected by the speed of the spacecraft, and the passage of time as it's affected by the gravity of the Earth itself, both special and general relativities. It's astonishing. We work very hard to measure time with all sorts of extraordinary clocks, but there is no question with our brains which are wet chemical computers we lose track of time. We don't know if sometimes it feels short, sometimes it feels long and it's just the nature I think of being constrained by measuring time with our brains. This is why we build instruments to measure time outside of ourselves externally.
BUONOMANO: The brain has been telling time since the dawn of animal species. So even plants have the ability to tell time in terms of Circadian clock. So it's reasonable to ask so is that how the brain tells time? Does the brain have some oscillator that's ticking away and some circuit that's counting those ticks and tocks. The answer is no. The brain seems to have fundamentally different ways of telling time. So the first thing to notice is that while the mechanical clocks that we make, even your quartz watch, can tell time across a vast range of scales from tens of milliseconds to hours, minutes and days and months and years. So, the brain has many different clocks in order to tell the milliseconds and seconds and to tell the time of day. So one way to think about it is the Circadian clock, the clock that tells you what time of day it is and when to rise and when to go to sleep. That doesn't have a minute hand, much less a second hand. In contrast, the clock that tells you, the timing device in your brain that tells you hmm, this red light is taking a bit too long to turn. This traffic light is taking a bit long to turn or I think the waiter forgot my coffee. That clock doesn't have an hour hand, much less a number of days that have gone by. So the brain has different areas, different mechanisms in order to tell time. We don't understand, fully understand how the brain tells you what the tempo is a song is or when the red light is going to change. But it doesn't seem to have to do with any oscillator counter mechanisms. It seems to do with neural dynamics which is the fact that patterns of neurons, neurons are coupled to each other, neurons are connected to each other. And when you activate some neurons that group of neurons can activate another group of neurons which can activate another group of neurons. So you can have these evolving patterns of neural activity. So, this is consistent with what we call the multiple clock principle which is the brain doesn't have any master clock. It has many different circuits, each specialized or that focuses on processing time on one scale or another.
THALLER: One thing we are absolutely sure of is that the rate of time does change. Time is not just simply a progression like a river that keeps flowing. It can change depending on how fast you're moving through space and this is Einstein's special Theory of Relativity. The idea is that the faster you go, the slower time appears to be moving for you if other observers look at you going by. As you go faster and faster and approach the speed of light your time slows down more and more. And the amazing thing is that at the speed of light time does not progress at all. There are more everyday applications to this too. For example, the global positioning satellites that allow you to take your location from your smartphone. Those satellites are going overhead very, very fast. They're going nearly 20,000 miles an hour. And it turns out that that's fast enough that their time is slowed down. They're actually in a slightly different timeframe than we are. And we have to account for that. We have to correct for that mathematically. Otherwise, you would not get the right location. So, we know that time slows down. We observe this happening all around us. It was a really hard thing in modern physics about a hundred years ago for people to let go of the idea that time just has a rate that it flows. That, in fact, it can flow at different rates for different observers. Then there's the question of what is time related to space. And you may have heard that Einstein talked about a concept called space-time. He didn't believe that space and time were separate things. We certainly perceive them differently in our human brains. We can move through space, but time always seems to go just in one rate and in one direction. But Einstein thought they were part of a fabric, they were woven together. And one of the ways he illustrated this was that you have to adjust space and time so they always kind of balance out. If I am not moving through space, I'm sitting here still in this chair, then time just seems to go forward at a natural rate and time just flows. But if I start going faster and faster, my time slows down. So, in a sense I'm moving through space very fast so I can't move through time as fast as I might have. The two balance each other, space-time. If you move through space very fast time begins to slow down. And now something gets even stranger and that is that Einstein thought that the beginning of the universe, the Big Bang, created all of space and all of time at once in a big whole something. So every point in the past and every point in the future are just as real as the point of time you feel yourself in right now. Einstein believed that literally. One of his best friends died and he wrote a letter to this person's wife talking about how his friend still exists. Time is a landscape and if you had the right perspective on the universe you would see all of it laid out in front of you. All past, present, and future as a whole thing. And he said, you know, your husband, my friend, is just over the next hill. He's still there. We can't see him where we are now, but we are on this landscape with him and he still exists just as much as he ever has. Einstein believed that you right now had been dead for trillions of years, but you haven't been born yet. That everything that's happened to you if you could get the right perspective on the universe you could see all at once.
BUONOMANO: The present is the notion is that only the present is real. The past was real, the future some configuration of the future universe will be real, but for now only the present is real. In contrast the opposing view is called eternalism. Eternalism you have the past, present and future are all equally real. So, that makes the present just an arbitrary point in time or an arbitrary moment in time. So one way to think about this is now is to time as here is to space. So in the same sense that I happen to be here and some viewers are out at some other point in space and we're all comfortable with that notion that other points in space are equally real, in eternalism you have to be comfortable with the notion that other moments in time are as equally real as this moment in time and this is just an arbitrary moment.
GLEICK: And so if a physicist comes to me and says do some readjustment. Face it, the future looks different from the past to you, but actually physics tells us it's the same. I at least acknowledge that I have an obligation to take that seriously, to listen to it. And physicists do argue about these things and it's fair to argue about it.
THALLER: So modern physics has required us to really let go of the idea of time as something that just flows. We can measure that it's changing around us all over the place – satellites, particle accelerators, anything going fast. And it may be that space and time are the same thing all wrapped up together and it all exists all at once.
- Everything we do as living organisms is dependent, in some capacity, on time. The concept is so complex that scientists still argue whether it exists or if it is an illusion.
- In this video, astrophysicist Michelle Thaller, science educator Bill Nye, author James Gleick, and neuroscientist Dean Buonomano discuss how the human brain perceives of the passage of time, the idea in theoretical physics of time as a fourth dimension, and the theory that space and time are interwoven.
- Thaller illustrates Einstein's theory of relativity, Buonomano outlines eternalism, and all the experts touch on issues of perception, definition, and experience.
- From Science Fiction to Physics: Does Time Actually Exist? - Big Think ›
- New controversial theory: Past, present, future exist simultaneously ... ›
- Time Might Not Exist Outside of Our Minds, Propose Scientists - Big ... ›
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How imagining the worst case scenario can help calm anxiety.
- Stoicism is the philosophy that nothing about the world is good or bad in itself, and that we have control over both our judgments and our reactions to things.
- It is hardest to control our reactions to the things that come unexpectedly.
- By meditating every day on the "worst case scenario," we can take the sting out of the worst that life can throw our way.
Are you a worrier? Do you imagine nightmare scenarios and then get worked up and anxious about them? Does your mind get caught in a horrible spiral of catastrophizing over even the smallest of things? Worrying, particularly imagining the worst case scenario, seems to be a natural part of being human and comes easily to a lot of us. It's awful, perhaps even dangerous, when we do it.
But, there might just be an ancient wisdom that can help. It involves reframing this attitude for the better, and it comes from Stoicism. It's called "premeditation," and it could be the most useful trick we can learn.
Broadly speaking, Stoicism is the philosophy of choosing your judgments. Stoics believe that there is nothing about the universe that can be called good or bad, valuable or valueless, in itself. It's we who add these values to things. As Shakespeare's Hamlet says, "There is nothing either good or bad, but thinking makes it so." Our minds color the things we encounter as being "good" or "bad," and given that we control our minds, we therefore have control over all of our negative feelings.
Put another way, Stoicism maintains that there's a gap between our experience of an event and our judgment of it. For instance, if someone calls you a smelly goat, you have an opportunity, however small and hard it might be, to pause and ask yourself, "How will I judge this?" What's more, you can even ask, "How will I respond?" We have power over which thoughts we entertain and the final say on our actions. Today, Stoicism has influenced and finds modern expression in the hugely effective "cognitive behavioral therapy."
Helping you practice StoicismCredit: Robyn Beck via Getty Images
One of the principal fathers of ancient Stoicism was the Roman statesmen, Seneca, who argued that the unexpected and unforeseen blows of life are the hardest to take control over. The shock of a misfortune can strip away the power we have to choose our reaction. For instance, being burglarized feels so horrible because we had felt so safe at home. A stomach ache, out of the blue, is harder than a stitch thirty minutes into a run. A sudden bang makes us jump, but a firework makes us smile. Fell swoops hurt more than known hardships.
What could possibly go wrong?
So, how can we resolve this? Seneca suggests a Stoic technique called "premeditatio malorum" or "premeditation." At the start of every day, we ought to take time to indulge our anxious and catastrophizing mind. We should "rehearse in the mind: exile, torture, war, shipwreck." We should meditate on the worst things that could happen: your partner will leave you, your boss will fire you, your house will burn down. Maybe, even, you'll die.
This might sound depressing, but the important thing is that we do not stop there.
Stoicism has influenced and finds modern expression in the hugely effective "cognitive behavioral therapy."
The Stoic also rehearses how they will react to these things as they come up. For instance, another Stoic (and Roman Emperor) Marcus Aurelius asks us to imagine all the mean, rude, selfish, and boorish people we'll come across today. Then, in our heads, we script how we'll respond when we meet them. We can shrug off their meanness, smile at their rudeness, and refuse to be "implicated in what is degrading." Thus prepared, we take control again of our reactions and behavior.
The Stoics cast themselves into the darkest and most desperate of conditions but then realize that they can and will endure. With premeditation, the Stoic is prepared and has the mental vigor necessary to take the blow on the chin and say, "Yep, l can deal with this."
Catastrophizing as a method of mental inoculation
Seneca wrote: "In times of peace, the soldier carries out maneuvers." This is also true of premeditation, which acts as the war room or training ground. The agonizing cut of the unexpected is blunted by preparedness. We can prepare the mind for whatever trials may come, in just the same way we can prepare the body for some endurance activity. The world can throw nothing as bad as that which our minds have already imagined.
Stoicism teaches us to embrace our worrying mind but to embrace it as a kind of inoculation. With a frown over breakfast, try to spend five minutes of your day deliberately catastrophizing. Get your anti-anxiety battle plan ready and then face the world.
A study on charity finds that reminding people how nice it feels to give yields better results than appealing to altruism.
- A study finds asking for donations by appealing to the donor's self-interest may result in more money than appealing to their better nature.
- Those who received an appeal to self-interest were both more likely to give and gave more than those in the control group.
- The effect was most pronounced for those who hadn't given before.
Even the best charities with the longest records of doing great fundraising work have to spend some time making sure that the next donation checks will keep coming in. One way to do this is by showing potential donors all the good things the charity did over the previous year. But there may be a better way.
A new study by researchers in the United States and Australia suggests that appealing to the benefits people will receive themselves after a donation nudges them to donate more money than appealing to the greater good.
How to get people to give away free money
The postcards that were sent to different study subjects. The one on the left highlighted benefits to the self, while the one on the right highlighted benefits to others.List et al. / Nature Human Behaviour
The study, published in Nature Human Behaviour, utilized the Pick.Click.Give program in Alaska. This program allows Alaska residents who qualify for dividends from the Alaska Permanent Fund, a yearly payment ranging from $800 to $2000 in recent years, to donate a portion of it to various in-state non-profit organizations.
The researchers randomly assigned households to either a control group or to receive a postcard in the mail encouraging them to donate a portion of their dividend to charity. That postcard could come in one of two forms, either highlighting the benefits to others or the benefits to themselves.
Those who got the postcard touting self-benefits were 6.6 percent more likely to give than those in the control group and gave 23 percent more on average. Those getting the benefits-to-others postcard were slightly more likely to give than those receiving no postcard, but their donations were no larger.
Additionally, the researchers were able to break the subject list down into a "warm list" of those who had given at least once before in the last two years and a "cold list" of those who had not. Those on the warm list, who were already giving, saw only minor increases in their likelihood to donate after getting a postcard in the mail compared to those on the cold list.
Additionally, the researchers found that warm-list subjects who received the self-interest postcard gave 11 percent more than warm-list subjects in the control group. Amazingly, among cold-list subjects, those who received a self-interest postcard gave 39 percent more.
These are substantial improvements. At the end of the study, the authors point out, "If we had sent the benefits to self message to all households in the state, aggregate contributions would have increased by nearly US$600,000."
To put this into perspective, in 2017 the total donations to the program were roughly $2,700,000.
Is altruism dead?
Are all actions inherently self-interested? Thankfully, no. The study focuses entirely on effective ways to increase charitable donations above levels that currently exist. It doesn't deny that some people are giving out of pure altruism, but rather that an appeal based on self-interest is effective. Plenty of people were giving before this study took place who didn't need a postcard as encouragement. It is also possible that some people donated part of their dividend check to a charity that does not work with Pick.Click.Give and were uncounted here.
It is also important to note that Pick.Click.Give does not provide services but instead gives money to a wide variety of organizations that do. Those organizations operate in fields from animal rescue to job training to public broadcasting. The authors note that it is possible that a more specific appeal to the benefits others will receive from a donation might prove more effective than the generic and all-inclusive "Make Alaska Better For Everyone" appeal that they used.
In an ideal world, charity is its own reward. In ours, it might help to remind somebody how warm and fuzzy they'll feel after donating to your cause.
Inventions with revolutionary potential made by a mysterious aerospace engineer for the U.S. Navy come to light.
- U.S. Navy holds patents for enigmatic inventions by aerospace engineer Dr. Salvatore Pais.
- Pais came up with technology that can "engineer" reality, devising an ultrafast craft, a fusion reactor, and more.
- While mostly theoretical at this point, the inventions could transform energy, space, and military sectors.
The U.S. Navy controls patents for some futuristic and outlandish technologies, some of which, dubbed "the UFO patents," came to life recently. Of particular note are inventions by the somewhat mysterious Dr. Salvatore Cezar Pais, whose tech claims to be able to "engineer reality." His slate of highly-ambitious, borderline sci-fi designs meant for use by the U.S. government range from gravitational wave generators and compact fusion reactors to next-gen hybrid aerospace-underwater crafts with revolutionary propulsion systems, and beyond.
Of course, the existence of patents does not mean these technologies have actually been created, but there is evidence that some demonstrations of operability have been successfully carried out. As investigated and reported by The War Zone, a possible reason why some of the patents may have been taken on by the Navy is that the Chinese military may also be developing similar advanced gadgets.
Among Dr. Pais's patents are designs, approved in 2018, for an aerospace-underwater craft of incredible speed and maneuverability. This cone-shaped vehicle can potentially fly just as well anywhere it may be, whether air, water or space, without leaving any heat signatures. It can achieve this by creating a quantum vacuum around itself with a very dense polarized energy field. This vacuum would allow it to repel any molecule the craft comes in contact with, no matter the medium. Manipulating "quantum field fluctuations in the local vacuum energy state," would help reduce the craft's inertia. The polarized vacuum would dramatically decrease any elemental resistance and lead to "extreme speeds," claims the paper.
Not only that, if the vacuum-creating technology can be engineered, we'd also be able to "engineer the fabric of our reality at the most fundamental level," states the patent. This would lead to major advancements in aerospace propulsion and generating power. Not to mention other reality-changing outcomes that come to mind.
Among Pais's other patents are inventions that stem from similar thinking, outlining pieces of technology necessary to make his creations come to fruition. His paper presented in 2019, titled "Room Temperature Superconducting System for Use on a Hybrid Aerospace Undersea Craft," proposes a system that can achieve superconductivity at room temperatures. This would become "a highly disruptive technology, capable of a total paradigm change in Science and Technology," conveys Pais.
High frequency gravitational wave generator.
Credit: Dr. Salvatore Pais
Another invention devised by Pais is an electromagnetic field generator that could generate "an impenetrable defensive shield to sea and land as well as space-based military and civilian assets." This shield could protect from threats like anti-ship ballistic missiles, cruise missiles that evade radar, coronal mass ejections, military satellites, and even asteroids.
Dr. Pais's ideas center around the phenomenon he dubbed "The Pais Effect". He referred to it in his writings as the "controlled motion of electrically charged matter (from solid to plasma) via accelerated spin and/or accelerated vibration under rapid (yet smooth) acceleration-deceleration-acceleration transients." In less jargon-heavy terms, Pais claims to have figured out how to spin electromagnetic fields in order to contain a fusion reaction – an accomplishment that would lead to a tremendous change in power consumption and an abundance of energy.
According to his bio in a recently published paper on a new Plasma Compression Fusion Device, which could transform energy production, Dr. Pais is a mechanical and aerospace engineer working at the Naval Air Warfare Center Aircraft Division (NAWCAD), which is headquartered in Patuxent River, Maryland. Holding a Ph.D. from Case Western Reserve University in Cleveland, Ohio, Pais was a NASA Research Fellow and worked with Northrop Grumman Aerospace Systems. His current Department of Defense work involves his "advanced knowledge of theory, analysis, and modern experimental and computational methods in aerodynamics, along with an understanding of air-vehicle and missile design, especially in the domain of hypersonic power plant and vehicle design." He also has expert knowledge of electrooptics, emerging quantum technologies (laser power generation in particular), high-energy electromagnetic field generation, and the "breakthrough field of room temperature superconductivity, as related to advanced field propulsion."
Suffice it to say, with such a list of research credentials that would make Nikola Tesla proud, Dr. Pais seems well-positioned to carry out groundbreaking work.
A craft using an inertial mass reduction device.
Credit: Salvatore Pais
The patents won't necessarily lead to these technologies ever seeing the light of day. The research has its share of detractors and nonbelievers among other scientists, who think the amount of energy required for the fields described by Pais and his ideas on electromagnetic propulsions are well beyond the scope of current tech and are nearly impossible. Yet investigators at The War Zone found comments from Navy officials that indicate the inventions are being looked at seriously enough, and some tests are taking place.
If you'd like to read through Pais's patents yourself, check them out here.
Laser Augmented Turbojet Propulsion System
Credit: Dr. Salvatore Pais
The 'Monkeydactyl' was a flying reptile that evolved highly specialized adaptations in the Mesozoic Era.
- The 'Monkeydactly', or Kunpengopterus antipollicatus, was a species of pterosaur, a group of flying reptiles that were the first vertebrates to evolve the ability of powered flight.
- In a recent study, a team of researchers used microcomputed tomography scanning to analyze the anatomy of the newly discovered species, finding that it was the first known species to develop opposable thumbs.
- As highly specialized dinosaurs, pterosaurs boasted unusual anatomy that gave them special advantages as aerial predators in the Mesozoic Era.
A newly discovered flying dinosaur nicknamed "Monkeydactyl" is the oldest known creature that evolved opposable thumbs, according to new research published in Current Biology.
The 160-million-year-old reptile is officially named Kunpengopterus antipollicatus. Discovered in China, the dinosaur was a darwinopteran pterosaur, a subgroup of pterosaurs, which first appeared 215 million years ago during the Triassic Period. Pterosaurs, like the pterodactyl, were the first vertebrates to evolve the ability of powered flight.
But unlike other pterosaurs, the Monkeydactyl was the only species in its group known to have opposable thumbs. It's a rare adaptation for non-mammals: The only extant examples are chameleons and some species of tree frogs. (Most birds have at least one opposable digit, though that digit is usually classified as a hallux, not a pollex, which means "thumb" in Latin.)
To analyze the anatomy of K. antipollicatus, an international team of researchers used microcomputed tomography scanning, which generates images of the inside of the body.
"The fingers of 'Monkeydactyl' are tiny and partly embedded in the slab," study co-author Fion Waisum Ma said in a press release. "Thanks to micro-CT scanning, we could see through the rocks, create digital models, and tell how the opposed thumb articulates with the other finger bones."
"This is an interesting discovery. It provides the earliest evidence of a true opposed thumb, and it is from a pterosaur — which wasn't known for having an opposed thumb."
As a tree-dwelling reptile, the Monkeydactyl probably evolved opposable thumbs so it could grasp tree branches, which would have helped it hang, avoid falls, and obtain food. This arboreal (tree-dwelling) locomotion would help the Monkeydactyl adapt to its home ecosystem, the subtropical forests of the Tiaojishan Formation in China during the Jurassic Period.
The researchers noted that the forests of the Tiaojishan Formation were likely warm and humid, thriving with "a rich and complex" diversity of tree-dwelling animals. But while the forests were home to multiple pterosaur species, the Monkeydactyl was likely the only one that was arboreal, spending most of its time in the treetops, while other pterosaurs occupied different levels of the forest.
K. antipollicatus and its phylogenetic position. (A and B) Holotype specimen BPMC 0042 (A) and a schematic skeletal drawing (B). Scale bars, 50 mm.Credit: Zhou et al.
This process — in which competing species manage to coexist by using the environment in different ways — is called "niche partitioning."
"Tiaojishan palaeoforest is home to many organisms, including three genera of darwinopteran pterosaurs," study author Xuanyu Zhou said in the press release. "Our results show that K. antipollicatus has occupied a different niche from Darwinopterus and Wukongopterus, which has likely minimized competition among these pterosaurs."
In general, pterosaurs are a prime example of how animals can evolve remarkably specialized adaptations. As pioneers of vertebrate flight, pterosaurs had strong and lightweight skeletons that ranged widely in size, with some boasting wingspans of more than 30 feet. The largest pterosaurs weighed more than 650 pounds and had jaws twice the length of Tyrannosaurus rex.
Unlike birds, which jump into the air using only their hind limbs, pterosaurs used their exceptionally strong hind limbs and forelimbs to push off the ground and gain enough launch power for flight. That these massive dinosaurs managed to fly, and did so successfully for about 80 million years, has long fascinated and puzzled scientists.The recent discovery shows that pterosaurs developed even more remarkable adaptations than previously thought, suggesting there's still more to learn about the "monsters of the Mesozoic skies."