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Will humans ever travel to different dimensions?

In Netflix’s "Stranger Things" characters enter a parallel dimension. Could this actually happen? 


Art installation portraying a portal to another dimension.

Netflix's gripping original series Stranger Things has many across the country itching for a second season. If you are science-minded or just innately curious, you may be wondering about the science behind this sci-fi/horror's plot. Could there be such a thing as a parallel dimension? Might we go there?

One problem, according to theoretical physicist Brian Greene of Columbia University, is that the show mixes up other dimensions with multiverse theory. We have a universe with three dimensions and if you include space-time, four. Einstein was the first to say that time and space are interrelated. Some physicists posit that there may be as many as ten dimensions inhabiting other universes, or this one. There may even be more.

If there are other dimensions, perhaps they are too small for us to see or are invisible. Or our brains are not made to perceive them. If they inhabit a parallel universe, we might have to go there to experience these dimensions before we can perceive them. At this stage, it's almost all theoretical.

Is there more than one Earth?

So in Stranger Things, characters don't travel to another dimension but rather another version of Earth in a parallel universe. Hypothetically, this holds true. If space-time goes on forever, it only makes sense that it must repeat itself. After all, particles can only arrange themselves in so many ways. Consider that right now, there may be an infinite number of clones out there of you, in an infinite number of universes. But each one would be slightly different.

The Big Bang occurred 13.7 billion years ago. That means the edge of our observable universe is 13.7 billion light years away. After that, another universe may bump up against it. This is part of the theory of "braneworlds" where multiple universes are layered one atop another like layers of rock. They may not remain parallel, but cross over in places, even overlap. Professor Greene, author of the book Hidden Reality, says that there may be, “..higher dimensional branes that overlap in a three dimensional subspace, and that overlap region might in fact be what we experience as reality."

Multiverse theory comes from Hugh Everett III, a Princeton postdoctoral student who in 1954 proposed the existence of parallel universes, behaving much like our own, all interconnected. But there are changes from one to another, changes in historical events or even how life on the planet evolved. In one version of Earth perhaps the Axis Powers won World War II, in another dinosaurs still roam the Earth and another still the dodo is thriving. This is all theoretical of course, but possible.

A black hole. It's theorized that they may be wormholes to parallel universes.

Everett developed his Many-Worlds Theory to try and fill holes in quantum physics, as a way to account for quantum matter's erratic behavior. For instance, photons which make up light can be observed as both particles and waves. How can this be? Then there's the Heisenberg Uncertainty Principle, where you can measure for the location of a particle or it's velocity but not both. There is also the radical Copenhagen interpretation, posited by Danish physicist Niels Bohr, where matter exists not in one but all forms simultaneously, known as superposition.

Bohr's idea especially influenced, Everett in his development of the multiverse theory. A photon may be a wave in one universe and a particle in another, which explains why quantum matter may be observed in different physical states. If this is true, it could be interpreted as movement taking place across different universes. Once considered speculative at best, an experiment in the 1990's called quantum suicide showed that Everett's theory is possible. Since then, several physics properties have been shown to support the multiverse theory. Some fascinating speculations branch off from it.

The theory of daughter universes focuses on probabilities. Here, a new universe splits off with every new action that occurs. Each possible branch accounts for a separate decision and the outcome that followed. Think about the most impactful moments of your life, where you had to make a serious decision. Now consider that whatever other choices were available, another you in another universe followed that path, instead. The more choices you have in a given situation, the more parallel universes are made. One snag, you cannot be aware of your other-world clones, not even upon their death. As far as you will ever know, you are the only you.

CERN, the largest physics lab in the world. Here physicists smash particles to bits and examine their makeup.

String Theory is a theory posited by American physicist Michio Kaku. This is an alternative to the Many-Worlds Theory. It relies on 11 different dimensions. Here, all matter that exists is made up of strings. Any physical forces that play upon the matter are actually the vibrations of these strings. Gravity and other forces can flow between universes. Unlike the braneworlds theory, in String Theory when they are not parallel, one universe might knock into another, creating a Big Bang, birthing a brand new universe. The one experiment set to prove the possibility ended in disappointment. But String Theory isn't out of the running yet. After elucidating the Theory of Relativity, Einstein spent the remainder of his life searching for the missing pieces which would explain how all physical processes operate, what physicists now call the, Theory of Everything.

Scientists through experimentation and observation are attempting to reverse engineer our universe, and reaching back inch-by-inch toward the Big Bang. They do so by discovering smaller and ever more elusive particles, and understanding those forces which we know exist better, such as when physicists were recently able to measure gravity. All of these efforts are in hopes of getting closer to a unified Theory of Everything. It could be that there are other universes and that we can travel from one to another. But we must first discover whether or not it is so and what properties they have, before we can discern how best to travel there.

To learn more about String Theory click here:

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Construction of the $500 billion dollar tech city-state of the future is moving ahead.

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Technology & Innovation
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Human brains remember certain words more easily than others

A study of the manner in which memory works turns up a surprising thing.

Image Point Fr / Shutterstock
Mind & Brain
  • Researchers have found that some basic words appear to be more memorable than others.
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Cognitive psychologist Weizhen Xie (Zane) of the NIH's National Institute of Neurological Disorders and Stroke (NINDS) works with people who have intractable epilepsy, a form of the disorder that can't be controlled with medications. During research into the brain activity of patients, he and his colleagues discovered something odd about human memory: It appears that certain basic words are consistently more memorable than other basic words.

The research is published in Nature Human Behaviour.

An odd find

Image source: Tsekhmister/Shutterstock

Xie's team was re-analyzing memory tests of 30 epilepsy patients undertaken by Kareem Zaghloul of NINDS.

"Our goal is to find and eliminate the source of these harmful and debilitating seizures," Zaghloul said. "The monitoring period also provides a rare opportunity to record the neural activity that controls other parts of our lives. With the help of these patient volunteers we have been able to uncover some of the blueprints behind our memories."

Specifically, the participants were shown word pairs, such as "hand" and "apple." To better understand how the brain might remember such pairings, after a brief interval, participants were supplied one of the two words and asked to recall the other. Of the 300 words used in the tests, five of them proved to be five times more likely to be recalled: pig, tank, doll, pond, and door.

The scientists were perplexed that these words were so much more memorable than words like "cat," "street," "stair," "couch," and "cloud."

Intrigued, the researchers looked at a second data source from a word test taken by 2,623 healthy individuals via Amazon's Mechanical Turk and found essentially the same thing.

"We saw that some things — in this case, words — may be inherently easier for our brains to recall than others," Zaghloul said. That the Mechanical Turk results were so similar may "provide the strongest evidence to date that what we discovered about how the brain controls memory in this set of patients may also be true for people outside of the study."

Why understanding memory matters

person holding missing piece from human head puzzle

Image source: Orawan Pattarawimonchai/Shutterstock

"Our memories play a fundamental role in who we are and how our brains work," Xie said. "However, one of the biggest challenges of studying memory is that people often remember the same things in different ways, making it difficult for researchers to compare people's performances on memory tests." He added that the search for some kind of unified theory of memory has been going on for over a century.

If a comprehensive understanding of the way memory works can be developed, the researchers say that "we can predict what people should remember in advance and understand how our brains do this, then we might be able to develop better ways to evaluate someone's overall brain health."

Party chat

Image source: joob_in/Shutterstock

Xie's interest in this was piqued during a conversation with Wilma Bainbridge of University of Chicago at a Christmas party a couple of years ago. Bainbridge was, at the time, wrapping up a study of 1,000 volunteers that suggested certain faces are universally more memorable than others.

Bainbridge recalls, "Our exciting finding is that there are some images of people or places that are inherently memorable for all people, even though we have each seen different things in our lives. And if image memorability is so powerful, this means we can know in advance what people are likely to remember or forget."

spinning 3D model of a brain

Temporal lobes

Image source: Anatomography/Wikimedia

At first, the scientists suspected that the memorable words and faces were simply recalled more frequently and were thus easier to recall. They envisioned them as being akin to "highly trafficked spots connected to smaller spots representing the less memorable words." They developed a modeling program based on word frequencies found in books, new articles, and Wikipedia pages. Unfortunately, the model was unable to predict or duplicate the results they saw in their clinical experiments.

Eventually, the researchers came to suspect that the memorability of certain words was linked to the frequency with which the brain used them as semantic links between other memories, making them often-visited hubs in individuals's memory networks, and therefore places the brain jumped to early and often when retrieving memories. This idea was supported by observed activity in participants' anterior temporal lobe, a language center.

In epilepsy patients, these words were so frequently recalled that subjects often shouted them out even when they were incorrect responses to word-pair inquiries.

Seek, find

Modern search engines no longer simply look for raw words when resolving an inquiry: They also look for semantic — contextual and meaning — connections so that the results they present may better anticipate what it is you're looking for. Xie suggests something similar may be happening in the brain: "You know when you type words into a search engine, and it shows you a list of highly relevant guesses? It feels like the search engine is reading your mind. Well, our results suggest that the brains of the subjects in this study did something similar when they tried to recall a paired word, and we think that this may happen when we remember many of our past experiences."

He also notes that it may one day be possible to leverage individuals' apparently wired-in knowledge of their language as a fixed point against which to assess the health of their memory and brain.


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