Podcast Summary
Understanding Time Through Different Perspectives: Time is a complex concept that can be perceived differently depending on the context, from a linear progression that can be altered to a more complex entity like a 'big ball of wibbly wobbly, tiny wimey stuff'.
Time, as we commonly understand it, is a complex concept that can be described in various ways through different perspectives. According to a question from a listener named Sean Karp, time can be seen as a linear progression that can be altered, like in Ray Bradbury's "A Sound of Thunder." However, in other contexts, such as in Star Trek or from a nonlinear, nonsubjective viewpoint, time can be thought of as a more complex entity, like a big ball of wibbly wobbly, tiny wimey stuff. Neil deGrasse Tyson explained that we can only truly understand time through how we measure it and the consequences different phenomena have on it. Colin Jost added a fascinating reference to Doctor Who, further emphasizing the multifaceted nature of time in popular culture and science fiction. Ultimately, the discussion highlighted the importance of considering various perspectives when trying to grasp the concept of time.
Time's non-linearity and black holes: The laws of relativity reveal time's flexibility, black holes distort it, and new theories may explain their mysteries
Time, as we commonly perceive it, is not strictly linear. The laws of relativity allow for time to be stretched or shrunk relative to other objects and even distorted in the presence of massive objects like black holes. These distortions are a result of the fabric of space-time being curved. Black holes, which are areas of extreme gravitational pull, do not suck in matter and energy and turn it into nothingness as previously thought. Instead, they likely collapse into a singularity, an infinitesimal point where our current understanding of physics fails. The future of understanding these phenomena lies in the development of new theories like string theory. Additionally, the concept of parallel universes and the possibility of time splitting remains a mystery.
Is the absence of time travelers proof that time travel is impossible?: Despite no evidence of time travelers in the present, the possibility of time travel into the future remains open due to the complexities and potential paradoxes involved.
The lack of evidence for time travelers in the present does not necessarily mean that time travel will never be possible in the future. During a discussion on StarTalk Radio, host Neil deGrasse Tyson and guest Colin Jost entertained various questions from listeners about time travel. One question posed was whether the absence of time travelers in the present proves that time travel cannot be invented. Tyson acknowledged that this is a valid point, but also suggested the possibility that time travelers might be hiding their existence or that time machines could only travel into the future. The conversation also touched on the idea that time travel could lead to paradoxes, making it a complex and intriguing concept. Ultimately, the discussion underscored the fascination and mystery surrounding time travel and the many questions it raises about the nature of time and the universe.
Considering both time and space for safe time travel: Properly designed time machines account for both time and space to ensure safe and intended travel, as space and time are interconnected and function as a single coordinate system in the universe, and altering past events could have unforeseen consequences.
Time travel involves both time and space. If you only travel back in time without considering your location, you could end up in space with no protection from the elements or in a different place entirely. A properly designed time machine would account for both time and space to ensure the traveler returns to the intended location and time. Additionally, space and time are interconnected and function as a single coordinate system in the universe. This means that travel through time also involves movement through space, making it essential to consider both when planning a time journey. Furthermore, altering even small events in the past could have significant consequences on who exists in the present or future. So, it's crucial to think carefully about the potential outcomes of any actions taken during time travel.
Orbits and Time Travel in the Universe: Orbits around the sun and galaxies impact time travel, requiring consideration of the sun's movement and potential wormholes for instantaneous travel.
Our celestial bodies, including Earth and the moon, orbit around each other and the sun, which in turn orbits the center of the galaxy. This intricate dance of orbits is an essential aspect of the universe. However, if one were to consider time travel, it's important to note that not only would one need to account for the 1-year increment, but also the sun's movement in its orbit around the galaxy. This means that even if you traveled exactly one year into the future, you would not end up in the same location on Earth due to the sun's position change. Furthermore, if we were to ponder the concept of folding two points of space-time together, we must understand that they wouldn't actually be in the same place, even if they appear close in a higher dimension. Instead, we can warp the fabric of space and time through a wormhole to travel instantaneously between them. Regarding the use of the sun's pull for time travel as depicted in Star Trek, it's theoretically possible to harness the sun's gravitational pull to achieve the necessary velocities. However, one must ensure a safe distance to avoid being pulled in by the sun's immense gravitational force. In summary, the universe's intricate orbital patterns and the potential for time travel require a deep understanding of physics and the ability to navigate through the fabric of space and time.
Using the sun's gravity for time travel is not feasible: The sun's gravity isn't strong enough for safe time travel and attempting it would likely destroy any spacecraft
While the concept of using the sun's gravity to increase velocity, as depicted in Star Trek 4, is intriguing, it's not scientifically feasible with our current understanding of physics. The sun doesn't have enough gravitational pull to create a safe enough slingshot effect for time travel. Additionally, any spacecraft attempting such a maneuver would be destroyed by the intense heat. To achieve time travel, we would need to encounter objects with much stronger gravitational forces, like black holes. However, even with these discoveries, the practicality of time travel remains a complex and unanswered question.
Gravity's Influence Depends on Mass and Distance: Mass and distance affect gravity: the moon, though less massive than Earth, makes us weigh more due to proximity to its center; Earth's size affects gravity too, with a larger Earth decreasing it.
Gravity is not just determined by an object's mass, but also by the distance to the center of that mass. For instance, although the moon has only 1/81st the mass of the Earth, we actually weigh more on the moon due to being closer to its center. This concept, described by Sir Isaac Newton, involves two opposing factors. If Earth were made bigger without increasing its mass, gravity would actually decrease. Conversely, being closer to a less massive object like the moon results in greater weight due to proximity to its center. Additionally, when discussing weight loss, it's essential to remember that people aim to lose mass, not just weight. Furthermore, an astronaut traveling to a black hole and back for three years might experience less time passing due to time dilation, but the elapsed time on Earth would depend on their speed.
Discovery of X-ray Binaries and Black Holes: Black holes, first discovered as x-ray binaries, emit intense radiation and challenge our understanding of time and space according to Einstein's relativity.
Black holes emit intense radiation, particularly in the form of x-rays, due to the material spiraling towards them. This phenomenon, known as "x-ray binaries," was first discovered in the 1960s and 1970s with the help of early x-ray telescopes. Cygnus X1, the first confirmed black hole, is located 6000 light years away, and to travel there in a year, a spacecraft would need to approach the speed of light, causing time to pass much slower for the traveler compared to those on Earth. This concept is explained by Einstein's theory of relativity, which states that time passes slower for objects moving at high speeds. In essence, the discovery of black holes and their associated x-ray emissions revolutionized our understanding of the universe.
Traveling Near a Black Hole: A Journey Through Time: Upon returning from a year near a black hole, one would find a world unrecognizable due to technological and societal advancements. Speculating about the future, Neil deGrasse Tyson ponders what might surprise us most, such as the absence of fossil fuel reliance or undiscovered discoveries.
If you were to travel near a black hole and spend a year there, you would age only three years while the rest of the world would have advanced 12,001 years. This means that upon your return, you would find yourself in a world almost unrecognizable, with technology and society having advanced beyond your wildest dreams or nightmares. Daniel Owens, a Facebook user, posed a more speculative question: what would be the most surprising thing not to find if one were to travel 100 years into the future? Neil deGrasse Tyson pondered this question, remarking that he would be embarrassed if an alien visited Earth today due to our reliance on fossil fuels and our propensity for conflict. However, he also noted that there might be things we take for granted that future civilizations might not have discovered yet. The possibilities are endless, making this a thought-provoking question indeed.
Harnessing Earth's Forces for Our Benefit: In the future, we should strive to utilize natural disasters and solar energy, rather than being at their mercy. Alien life and the Higgs boson particle were also discussed in relation to our technological advancements.
Despite the technological advancements in the 21st century, humanity is still not in control of natural disasters and earth's forces that could potentially harm us. One hundred years from now, our goal should be to harness the energy from these forces, such as volcanoes, hurricanes, and even solar energy that is currently wasted. The discussion also touched upon the possibility of alien life and how they might perceive us based on our current state of technology. The Higgs boson particle was brought up, but it's not clear yet if it could affect time travel. Overall, the conversation emphasized the importance of being in command of earth's forces and not being at their mercy.
The transformative power of particle physics: Scientific discoveries can have far-reaching implications and potential uses beyond our current comprehension, even if they seem frivolous at first.
Potential awe-inspiring and transformative power of particle physics. Neil deGrasse Tyson used the analogy of a Higgs boson spa, which could theoretically change a person's mass upon entering and exiting, to illustrate this concept. While the idea of using such a discovery for commercial weight loss purposes might seem frivolous, it highlights the human tendency to seek practical applications, even in the realm of scientific advancement. Ultimately, the pursuit of knowledge and understanding of the universe should be the primary goal, but it's important to remember that scientific discoveries can have far-reaching implications and potential uses beyond our current comprehension. As Neil deGrasse Tyson reminded us, "You've been listening to StarTalk Radio. I'm Neil deGrasse Tyson signing off as always, bidding you to keep looking up."
