What would I do if I could time travel?
10 Things I Would Do If I Could Time Travel
- Witness a couple monumental moments.
- Talk to my favorite artists.
- Find first editions of my favorite books.
- Say hello to the pets I have lost.
- Give some advice to my younger self.
- Have dinner with all of my grandparents.
- See what my parents were like when they were my age.
- See what my fiance was like before I met him.
What is the history of the time travel?
Time travel is a widely recognized concept in philosophy and fiction, particularly science fiction. The idea of a time machine was popularized by H. G. Wells’s 1895 novel The Time Machine. It is uncertain if time travel to the past is physically possible.
Where can I travel back in time?
18 places to go back in time
- Smicksburg, Pennsylvania, USA.
- Xinye Village, China.
- Den Gamble By, Århus, Denmark.
- Tombstone, Arizona, USA.
- Etar Architectural-Ethnographic Complex, Bulgaria.
- Kizhi, Russia.
- Shikoku Mura, Japan.
- Zuiderzeemuseum, Enkhuizen, The Netherlands.
What is the speed of dark?
Darkness travels at the speed of light. More accurately, darkness does not exist by itself as a unique physical entity, but is simply the absence of light.
Does light have mass?
Light is composed of photons, so we could ask if the photon has mass. The answer is then definitely “no”: the photon is a massless particle. According to theory it has energy and momentum but no mass, and this is confirmed by experiment to within strict limits.
Why is light affected by gravity if it has no mass?
It might be surprising to you to hear that gravity can affect light even though light has no mass. According to general relativity, gravity is actually caused by a curving of space and time. Since light travels in a straight line through straight spacetime, the curving of spacetime causes light to follow a curved path.
What particle has no mass?
gauge bosons
What are light waves called?
DESCRIBING ELECTROMAGNETIC ENERGY The terms light, electromagnetic waves, and radiation all refer to the same physical phenomenon: electromagnetic energy. This energy can be described by frequency, wavelength, or energy.
What type of waves are light waves?
The most common transverse and longitudinal waves are light waves and sound waves, respectively. All electromagnetic waves (light waves, microwaves, X-rays, radio waves) are transverse.
What color has the shortest wavelength?
violet light
Is light a particle?
Light behaves mainly like a wave but it can also be considered to consist of tiny packages of energy called photons. Photons carry a fixed amount of energy but have no mass.
Why is light not a particle?
Because photons are discrete particles, they have a certain amount of energy, but not a wavelength because they are not waves. Before that, Isaac Newton had claimed that light was really a stream of particles, but he did not have much evidence. Young made a clear case by demonstrating that light interferes with itself.
How did Einstein prove that light was a particle?
Einstein proved his theory by proving that the Planck’s constant he derived based on his experiments on the photoelectric effect exactly matched the constant 6.6260755 x 10-34 (Planck’s constant) that German physicist Max Planck (1858 to 1947) obtained in 1900 through his research on electromagnetic waves.
Why is light an electromagnetic wave?
Light as a wave: Light can be described (modeled) as an electromagnetic wave. In this model, a changing electric field creates a changing magnetic field. This changing magnetic field then creates a changing electric field and BOOM – you have light. So, Maxwell’s equations do say that light is a wave.
Is current an electromagnetic wave?
2 Answers. Electric current is the movement of electric charge through a conductor. An electromagnetic wave does not require a conductor. Electromagnetic waves are created by moving electric charges, but once created, they can propagate through a vacuum.
Is light electromagnetic energy?
Radio waves, gamma-rays, visible light, and all the other parts of the electromagnetic spectrum are electromagnetic radiation. Electromagnetic radiation can be described in terms of a stream of mass-less particles, called photons, each traveling in a wave-like pattern at the speed of light.
Is all light radiation?
Visible light is carried by photons, and so are all the other kinds of electromagnetic radiation like X-rays, microwaves and radio waves. In other words, light is a particle.
What are the 4 types of radiation?
Now, let’s look at the different kinds of radiation. There are four major types of radiation: alpha, beta, neutrons, and electromagnetic waves such as gamma rays. They differ in mass, energy and how deeply they penetrate people and objects.
What are 4 types of radiation from the sun?
All of the energy from the Sun that reaches the Earth arrives as solar radiation, part of a large collection of energy called the electromagnetic radiation spectrum. Solar radiation includes visible light, ultraviolet light, infrared, radio waves, X-rays, and gamma rays.
Is all radiation harmful?
Some examples of radiation include sunlight, radio waves, x-rays, heat, alpha, beta, gamma ionizing radiation, and infrared, just to name a few. Not all of these types of radiation are harmful, in fact, in moderation, most radiation will not pose a health risk.
What kind of radiation is harmful?
Gamma rays are the most harmful external hazard. Beta particles can partially penetrate skin, causing “beta burns”. Alpha particles cannot penetrate intact skin. Gamma and x-rays can pass through a person damaging cells in their path.
What gives off radiation in the home?
In homes and buildings, there are radioactive elements in the air. These radioactive elements are radon (Radon 222), thoron (Radon 220) and by products formed by the decay of radium (Radium 226) and thorium present in many sorts of rocks, other building materials and in the soil.
How can you protect yourself from radiation?
Staying inside will reduce your exposure to radiation.
- Close windows and doors.
- Take a shower or wipe exposed parts of your body with a damp cloth.
- Drink bottled water and eat food in sealed containers.
Time travel is actually somewhat unique in science fiction. Many core concepts have their origins earlier in history. But time travel is different. The first real work to envisage travelling in time was The Time Machine by HG Wells, which was published in 1895.
What are the benefits of time travel?
The ability to time-travel mentally has allowed us to imagine different futures and to produce the complex world we live in today. By recombining old memories, we are able to project ourselves forward in time, giving us endless combinations from which to select the most plausible possibilities.
Can we travel in time to past?
Time travel to the past is theoretically possible in certain general relativity spacetime geometries that permit traveling faster than the speed of light, such as cosmic strings, traversable wormholes, and Alcubierre drives.
Can a time machine be made?
Travelling in time might sound like a flight of fancy, but some physicists think it might really be possible. BBC Horizon looked at some of the most promising ideas for turning this staple of science fiction into reality. Ron Mallett has a dream: He wants to travel in time.
Did Einstein predict black holes?
Einstein denied several times that black holes could form. In 1939 he published a paper that argues that a star collapsing would spin faster and faster, spinning at the speed of light with infinite energy well before the point where it is about to collapse into a Schwarzchild singularity, or black hole.
Is general relativity proven?
General relativity has also been confirmed many times, the classic experiments being the perihelion precession of Mercury’s orbit, the deflection of light by the Sun, and the gravitational redshift of light. Other tests confirmed the equivalence principle and frame dragging.
What Einstein said about black hole?
Black holes, according to Albert Einstein’s theory of gravity, can have just three characteristics — mass, spin and charge. If those values are the same for any two black holes, it is impossible to discern one twin from the other. Black holes, they say, have no hair.
Who found out about black holes?
Roger Penrose (left) proved black holes are real objects. Andrea Ghez (center) and Reinhard Genzel (right) showed that one weighing 4 million times as much as the Sun lurks in the heart of our galaxy. Since Penrose’s advances, astronomers have found a wealth of evidence for black holes.
Has anyone been in a Blackhole?
Fortunately, this has never happened to anyone — black holes are too far away to pull in any matter from our solar system. But scientists have observed black holes ripping stars apart, a process that releases a tremendous amount of energy.
Can a black hole kill you?
The point at which tidal forces destroy an object or kill a person will depend on the black hole’s size. For small black holes whose Schwarzschild radius is much closer to the singularity, the tidal forces would kill even before the astronaut reaches the event horizon.
Can a black hole die?
It’s not much since a typical black hole will emit only one particle every year, but it’s not nothing. A good size black hole — say, a few times more massive than the sun — will take about 10^100 years to eventually evaporate through this process, known as Hawking Radiation.
What can kill a black hole?
There is nothing we could throw at a black hole that would do the least bit of damage to it. Even another black hole won’t destroy it– the two will simply merge into a larger black hole, releasing a bit of energy as gravitational waves in the process.
Do we live in black holes?
Black Holes All the Way Down We can’t calculate what happens in a black hole’s singularity — the laws of physics literally break down — but we can calculate what happens on the boundary of an event horizon. We might live in a universe within a black hole within a universe within a black hole.
How long can a black hole last?
If black holes evaporate under Hawking radiation, a solar mass black hole will evaporate over 1064 years which is vastly longer than the age of the universe. A supermassive black hole with a mass of 1011 (100 billion) M ☉ will evaporate in around 2×10100 years.
What would happen if a black hole hit Earth?
If a black hole were to form from the Earth itself, it would create an event horizon just 1.7 centimeters in diameter. Eventually, some time later, any object at rest — no matter how far away from the event horizon it initially was — will cross that horizon and encounter the central singularity.
What happens when two black holes collide?
When two black holes spiral around each other and ultimately collide, they send out gravitational waves – ripples in space and time that can be detected with extremely sensitive instruments on Earth. If confirmed, it would be the first known light flare from a pair of colliding black holes.
What would happen if 2 galaxies collide?
The merging of galaxies will radically affect their shape. For example, two spiral galaxies can merge and form an elliptical galaxy. Sometimes even more than two galaxies can collide with each other. Merging galaxies can also trigger the creation of new stars.
What happens when two planets collide?
If two planets pass closely by one another in orbit, one can perturb the other, resulting in a massive orbital change. These two planets could collide, one of them could get ejected, or one could even get hurled into their central star.
Will the earth ever collide with another planet?
Could a planet ever collide with Earth? Scientists say it’s highly unlikely. While large-scale collisions were prevalent when our solar system was young, it would be extremely rare for one to occur in a stable and established system like our own.
What is the biggest star?
UY Scuti
How long does a day last when Earth is first formed?
1.7 billion years ago the day was 21 hours long and the eukaryotic cells emerged. The multicellular life began when the day lasted 23 hours, 1.2 billion years ago. The first human ancestors arose 4 million years ago, when the day was already very close to 24 hours long.
How many hours exactly is a day?
23 hours
Do days actually get longer?
For us on the northern part of Earth, the shortest day comes at the solstice. After the winter solstice, the days get longer, and the nights shorter. Earth has seasons because our world is tilted on its axis with respect to our orbit around the sun.
How long was a day during dinosaurs?
They indicate that 620 million years ago the day was 21 hours, says Dr Mardling. Since the dinosaurs lived during the Mesozoic era, from 250 million years ago to 65 million years ago, day length would have been longer than this — probably closer to 23 hours.
What did Earth look like during the dinosaurs?
The Earth had heavy vegetation near costs, lakes, and rivers, but desert in its interior. During the Jurassic Period, the continents gradually broke apart. The world was warm, moist, and full of green plants. During the Cretaceous Period, most of the continents had separated.
When did last dinosaurs die?
about 65 million years ago
How long was a day 6 billion years ago?
They indicate that 620 million years ago the day was 21 hours, says Mardling. Since the dinosaurs lived during the Mesozoic era, from 250 million years ago to 65 million years ago, day length would have been longer than 21 hours and probably closer to 23 hours.