Causes and Effects of Gravity

Gravitational Force
“’You may hate gravity, but gravity doesn’t care.’ Clayton Christensen”. This Harvard teacher was directing this quotation to students like me because it is a force that cannot be viewed. Gravity is a field force exerted by an object to attract another object towards its center. In a simplified manner, it is an intangible, non-contact force that cannot be seen, but is existent between all objects. Gravitational force in a mathematical perspective is the mass of an object multiplied by gravitational acceleration. It is one of the fundamental forces of the universe that maintains planets, solar systems and galaxies. In the last couple of centuries, gravity became understood through Galileo, Brahe, Kepler, Newton and Einstein.

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Before the last 300 years, some only superficially understood gravity and others neglected the concept of having a field. In ancient times, civilizations believed that the skies and systems were held by divine power. Over they years, loads of scientists and philosophers tried to explain such a ‘magical’ phenomenon. In 1610, Galileo created a modern telescope. He used it to observe different planets’ behaviors. He focused on Earth and Venus; consequently he realized that they both revolve around the sun in a similar pattern. Therefore, he concluded that there’s a force that causes this spectacle. In the same time existed Kepler and Brahe. Kepler used Brahe’s astronomical data to conclude that planets revolve around the sun in an elliptical motion and that Earth has the same orbits around the sun; thus, he discovered that gravity creates seasons. Then, came the father of physics and creator of laws of motion, Isaac Newton. He was one of the first to explain the theory of mutual interaction, through his law of Universal Gravitation. It states that any and every two bodies in the universe attract each other with a force directly proportional to their masses and inversely proportion to the square of the distance between them. Thus objects like Newton’s apple is pulled to the earth and vice versa; the earth and planets are pulled towards the sun and vice versa. Finally, Albert Einstein, who is the most renounced genius, proposed a new theory. He said that gravity is the result of space and time being bent, general theory of relativity. He also theorized that enormous masses alter space and time because they deflect light, thus creating gravity. Skeptics denounced his theory, but time proved this theory right when astronauts went to space and found out that a clock is quicker away from earth.
There are many misconceptions about gravity because there are many different explanations to it. First, people think that gravitational force doesn’t exist between humans, but it does exist between every object in the universe. However, the gravitational pull by earth is much stronger than the force exerted by humans because of its huge mass. Second, some thinks that gravity occurs through a mixture of gases, the air. However, gravity occurs between planets and suns, where there is no air, vacuum. Third some think that gravitational acceleration (a=f/m) in free-fall decreases because of the force of gravity of other objects. However, air pressure causes this occurrence but gravitational acceleration is constant at 9.81 m/s. Fourth, people claim that we are supposed to be pulled to mars or the moon also. On the other hand, they don’t take into consideration the factor of distance and that earth is we are too far from the moon or mars. Fifth, some say that there is no gravitational force between Pluto and Earth. This is not true because gravitational force exists between all the objects in the universe. No matter how minute it can be, it is never zero. Sixth, a person might claim that his mass changes on the moon, but mass is constant; it is weight that changes depending on the gravitational pull. Seventh, one would think that we must be pulled to the Earth’s core since that is stated in Newton’s law of universal gravity. However, Newton also said in his third law that the Earth’s floor has an equal and opposing force to the gravitational force. Finally, one could claim that there is no gravitational force exerted on bacteria since they float. This statement is false because its mass is insignificant, gravitational force exerted by Earth on them is very small that it seemingly doesn’t affect them.
Gravity has a very strange nature since Isaac Newton and Albert Einstien explained it in different ways. They both agreed on some fundamentals. First of all, Gravity is a field force because it is a contact force that occurs without objects physically touching. For example, the Earth pulls a ball towards the ground without touching it. Moreover, they both agreed that gravity is of extreme importance, in which it holds planets in solar systems and solar systems in galaxies. Isaac Newton theorized that gravity is the tendency of an object to be pulled towards the center of another object. Newton proposed the equation that the force of gravity equates to the mass of an object multiplied by the gravitational acceleration. On the other hand, Albert Einstein explained gravity as the bend in space and time created by a huge mass, so other objects that come near, fall in the dip or orbit in one of the levels of the dip. He proposed the equation of the gravitational force equates to the gravitational constant multiplied by mass of object one times the mass of object two, all divided by the square of the radius.
One other point that all scientists that understood gravity agreed on is that the range of gravity is infinite. There are many misconceptions about its range because the thought of infinite is tough for all humans. However, there is a force of gravity between any two masses. For example gravity exists on an atomic level and on a intergalactic level.
There is an infinite amount of uses of gravity. On Earth, it keeps humans, animals and plants in the atmosphere stuck to the Earth’s surface. Also, gravity plays an important role in maintaining our spine’s shape because its God given strength is just right to neither make the spine neither rough nor soft. Furthermore, gravity keeps the Earth at a certain distance form the sun, so we would have suitable weather conditions to survive. Also, it pulls rain and flowing water downwards for us to drink water. Finally, it has a huge effect on the macro-organisms. Gravity keeps moons around their planets, planets around their stars; it keeps all systems in their galaxies and keeps galaxies in their clusters.
Therefore, we have passed through many stages to understand such a strange phenomenon. Many scientists and thinkers had their say like Newton and Einstein. They proposed different theories but all had the same fundamental, which is that gravity observed everywhere we look; it can be clearly seen on a macro-level, but it is existent between everything in the universe. Finally, there are many applications and misconceptions of gravity because of its unbounded nature. As Albert Einstein once said, “Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning.” This is the scientist’s code, which explains the constant advancements in science, chemistry and physics, and it will infinitely continue as people continue trying to ask the right questions.
Works cited
“Chapter 5.” Cohen Physics 131. N.p.: Cohen, n.d. N. pag. Print. http://www.esu.edu/physics/cohen/phys131/textbook/cohen_ch5.pdf>
“Gravitational Force.” Gravitational Force. PHY, n.d. Web. 19 Nov.2013. http://www.phy.syr.edu/courses/tutorials/FreeBody/Gravity/Gravitational.Force.html>.
“History of Gravity.” History of Gravity. WISC, n.d. Web. 19 Nov. 2013. http://www.physics.wisc.edu/museum/Exhibits-1/Mechanics/GravPit/index_HistGrav-2.html>.
Thompson, Hobbie, and Sarah Havern. “Gravity.” Gravity. Stanford, n.d. Web. 18 Nov. 2013. http://www.stanford
 

Concepts of Time Travel: Wormholes, Gravity and Blackholes

Any sort of time travel to the past through wormholes or any viable strategy is presumably incomprehensible, generally mysteries might happen. So unfortunately, it seems that time travel to the past will never happen; a bafflement for dinosaur seekers and an easing for antiquarians.
How to travel in future?
Through wormholes:
We should enjoy a little science fiction for a minute. Time travel motion pictures regularly offer an immense, vitality hungry machine. The machine makes a way through the fourth measurement, a tunnel through time. A time traveler, youthful hearted, a fearless, maybe reckless individual, ready for who realizes what, steps into the time tunnel and rises who knows when. The idea may be outlandish, and the actuality may be altogether different from this, yet the thought itself is not so insane. As should be obvious these films from a century ago are continually providing for some mind boggling and exceptional plans to individuals.
In this way, much the same as those motion pictures physicists have been contemplating tunnels in time, dark gaps and going at the rate of light,
However they take a stab at it from an alternate edge. They think about whether gateways to the past or what’s to come could ever be conceivable inside according to laws of nature. So, they think they seem to be. Additionally, they have even provided for them a name: WORMHOLES. The reality of the situation is that wormholes are surrounding us, just they’re so little there is no option see. Wormholes are extremely minor. They happen in niches and crevices in space and time.

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A wormhole is a hypothetical “tunnel” or alternate route, anticipated by Einstein’s hypothesis of relativity, that connections two spots in space-time – envisioned above, where negative vitality pulls space-time into the hole of a tunnel, rising in an alternate universe. This have been utilized as a part of movies as conductors for time travel – in Star-door, for instance, including gated tunnels between two different universes, and in two different Time times.
It’s much the same as a tunnel/connect between two structures; think about 2 persons need to go from first building’s top carpet to the other’s, individual a picked the tunnel and he arrived at rapidly as contrasted with the second individual who first went down and after that entered in second building and took a lift for top floor. Much the same as those tunnels wormholes are tunnels between two separate periods of space-time fabric.
Nothing is level or strong. In the event that you gaze nearly enough toward anything you’ll discover openings and wrinkles in it. It’s an essential physical rule, and it even applies to time. Actually something as smooth as nails has small openings, wrinkles and voids. Notwithstanding its not difficult to show that this is correct in the initial three sizes. Anyhow as stated by Einstein, its likewise valid for the fourth extent. There are little openings, wrinkles and voids in time. They are more diminutive even than sand, littler than particles. Small tunnels or easy routes through space and time always structure, vanish, and change inside this smaller than usual micro world. Furthermore they really interface two separate spots and two separate times, as should be obvious above in.
What’s more if by one means or another through enough power and propelled innovation, a goliath wormhole will have been built in space so that our spaceship (time machine) could go through it. It might be a sincerely astonishing gadget. One end could be here close Earth, and the other far, far away, close to some removed planet.
Hypothetically, a period tunnel or wormhole could do significantly more than take us to different planets. In the event that both finishes were in the same place, and differentiated by time rather than separation, a boat could fly in and turn out still close Earth, yet in the inaccessible past. Possibly Mughal Emperors might witness the boat coming in for an arriving or in future where we might meet our amazing grand grand kids.
HOW THEY ARE USELESS?
They remain just theoretical, as clearly no one has ever seen one, lamentably, these genuine time tunnels are simply a billion-trillion-trillionths of a centimeter (10^-33cm) over. Much excessively little for a human to pass through, yet here’s the place the thought of wormhole time machines is heading. A few researchers think it may be conceivable to catch a wormhole and extend it numerous trillions of times to become showbiz royalty enough for a man or even any travelling object to enter.
At the same time, to do so they require extremely enormous measure of vitality, for a wormhole something like 1 meter over, huge enough to fit an individual, you’d require a Jupiter’s value of mass changed over into vitality, and beyond any doubt its unimaginable and almost incomprehensible.
We should think about on the off chance that it is conceivable to do it, yet according to Stephen Hawking:
Wormhole like this much big can’t exist. What’s more the explanation behind that is reaction. If you ever went to any concert, you’ll presumably distinguish this shrieking clamor. It’s reaction. What causes it is basic. Sound enters the amplifier. It’s transmitted along the wires, made louder by the enhancer, and turns out at the speakers. However in the event that excessively of the sound from the speakers about-faces into the mic it goes around and around in a circle getting louder each one time. In the event that nobody stops it, criticism can wreck the sound framework.
The same problem will occur with a wormhole, just with radiation rather than sound. When the wormhole stretches, characteristic radiation will enter it, and wind up in a circle. The reaction will get to be so solid it obliterates the wormhole. So despite the fact that little wormholes do exist, and it may be conceivable to blow up one sometime, it won’t keep going long enough to be useful as a time machine.”
So time travel through wormhole is not conceivable.
Be that as it may the story’s not over yet. This doesn’t set aside a few minutes travel incomprehensible.
TIME TRAVEL THROUGH GRAVITY and BLACK HOLES:
Time streams like a stream and it appears to be as though each of us is conveyed persistently along by time’s current. Anyhow time is similar to a waterway in an alternate way. It streams at distinctive speeds in better places and that is the way to going into what’s to come. This thought was initially proposed by Albert Einstein in excess of 100 years prior. He understood that there ought to be places where time backs off, and others where time accelerates. He was completely right.
GPS, A system of satellites is in circle around Earth. The satellites make satellite route conceivable. Be that as it may they likewise uncover that time runs speedier in space than it does down here on Earth. Inside every rocket is an extremely exact clock. At the same time in spite of being so precise, they all increase around a minor of a second consistently. The framework need to right for the float, generally that modest contrast might steamed the entire framework, bringing about every GPS gadget on Earth to go out by something like six miles a day. You can simply envision the pandemonium that that might bring about.
The issue doesn’t lie with the timekeepers. They run quick on the grounds that time itself runs speedier in space than it does down beneath. Furthermore the explanation behind this uncommon impact is the mass of the Earth. Einstein understood that matter delays time and eases it off like the moderate some piece of a waterway. The heavier the item, the more it delays time. Also this startling actuality is the thing that opens the avenue to the likelihood of time travel to what’s to come.
Planets don’t impact excessively on time, we need something truly colossal and enormous body to make the range more curvy so time pass more gradually. The gravity which must be thousand times more amazing than sun.
Right in the focal point of the Milky Way, 26 thousands light years from us, lies the most heaviest protest in the system. It is a super-enormous dark gap holding the mass of four million suns smashed down into a solitary point by its gravity. The closer you get to the dark gap, the stronger the gravity. Get truly close and not even light can find a way to get escape. A dark opening like this one has an emotional impact on time, easing it off significantly more than whatever else might be available in the universe. That sets aside a few minutes machine.
Presently simply envision how a spaceship/time machine could have the capacity to exploit this wonder, by circling it. On the off chance that a space office were controlling the mission from Earth they’d watch that each one full circle took 16 minutes. At the same time for the fearless individuals ready for, to this gigantic item, time might be backed off. Furthermore here the impact might be significantly more great than the gravitational force of Earth. The team’s opportunity might be backed off significantly. For like clockwork circle, they’d just encounter eight minutes of time.
Around and around they’d set out for some, encountering simply a fraction of the time of everybody far from the dark gap. The boat and its group might be going through time. Envision they surrounded the dark gap for five of their years. Ten years might pass somewhere else. When they returned home, everybody on Earth might have matured five years more than they had.
So as stated by researcher super-huge dark gap is a time machine.
How is it impossible?
At the same time obviously, its not precisely commonsense. It has favorable circumstances over wormholes in that it doesn’t incite mysteries. Also it won’t annihilate itself in a blaze of criticism. At the same time its really risky. It’s far away and it doesn’t even take us far into what’s to come. We have to go at the pace of light for 26,000 years to get close to them. What’s more again to do so we don’t have enough vitality and life compass. The other point is that on the off chance that we go close to the dark opening, we will fall in it as it has extraordinary gravity that not even light can escape from it.
The given focuses demonstrate that time travel through dark gaps is additionally outlandish.
Luckily there is an alternate approach to go in time. What’s more this speaks to researchers last and best any expectation of building a time machine.
TIME TRAVEL And speed of light:
You simply need to travel, quick; much quicker even than the rate needed to abstain from being sucked into a dark opening. This is because of an alternate weird reality about the universe. There’s an inestimable rate confine, 186,000 miles for every second or 299,792,458 meter for every second, otherwise called the velocity of light. Nothing can surpass that speed. It’s their one of the best settled standards in science. Accept it or not, as stated by researchers going at close to the pace of light transports you to what’s to come.
To demonstrate why, how about we think up a science-fiction transportation framework. Envision a track that goes all around Earth, a track for a fastest train. We’re going to utilize this nonexistent train to get as close as could be allowed to the pace of light and perceive how it turns into a time machine. Ready for travelers with a restricted ticket to what’s to come. The train starts to quicken, quicker and speedier. Before long its circumnavigating the Earth again and again.
To approach the rate of light means surrounding the Earth really quick. Seven times each second. Be that as it may regardless of what amount of force the train has, it can never fully achieve the rate of light, since the laws of physical science deny it. Rather, we should say it draws near, only a tiny bit short of that extreme rate. Notwithstanding something phenomenal happens. Time begins streaming gradually ready for to whatever remains of the world, much the same as close to the dark opening, just all the more so. Everything on the train is in moderate movement.
This happens to ensure as far as possible, and its not tricky to see why. Envision a kid running advances up the train. Her send pace is added to the velocity of the prepare, so would she be able to break as far as possible basically by mishap? The response is no. The laws of nature keep the likelihood by backing off time locally available.
Notwithstanding she can’t run quick enough to break the utmost. Time will constantly ease off only enough to ensure as far as possible. Also from that certainty comes the likelihood of voyaging numerous years into what’s to come.
Envision that the train left the station on February 1, 2020. It rings Earth again and again for 100 prior years at long last stopping on New Year’s Day, 2120. The travelers will have just existed one week in light of the fact that time is backed off that much inside the train. When they got out they’d discover an altogether different world from the one they’d cleared out. In one week they’d have voyage 100 years into what’s to come.
Last hope also DIED:
Again we require a lot of vitality to move at velocity of light, vitality at any rate equivalents to the half vitality of universe. Besides, as stated by Einstein the quicker you go the heavier you get and additionally, on the off chance that we see the equation of motor vitality K.e=(1/2)mv^2, where “m” is the mass of anyone and “v” is its speed. Also this recipe says that our dynamic vitality is specifically relative to the square of our speed, which implies that motor vitality of an item builds because of the movement of that question.
Also I believe that moving at any pace does not have any effect. Implies it doesn’t make a difference from what speed you are moving, there will be no impact on time, of course, that is one man’s feeling.
In this way, obviously, fabricating a prepare that could arrive at such a velocity is truly outlandish. Anyway we have manufactured something exceptionally like the train at the world’s biggest atom smasher at CERN in Geneva, Switzerland.
Profound underground, in a roundabout tunnel 16 miles in length, is a stream of trillions of small particles. At the point when the force is turned on the quicken from zero to 60,000mph in a small amount of a second. Increment the force and the particles go speedier and quicker, until they’re zooming around the tunnel 11,000 times each second, which is just about the velocity of light. At the same time much the same as the train, they never entirely achieve that extreme rate. They can just get to 99.99 for every penny of the farthest point. At the point when that happens, they excessively begin to go in time. We know this in view of some to a great degree fleeting particles, called pi-mesons. Customarily, they deteriorate after only 25 billionths of a second. However when they are quickened to close light speed they keep going 30 times longer.
Well they have demonstrate about it, yet as they are moving those particles almost at velocity of light so there is a huge impact on their vitality level, and most presumably because of progress in vitality those particles change their properties. Henceforth, they keep going 30 times longer because of this reason.
It truly is that basic. In the event that we need to go into what’s to come, we only need to go quick. Truly quick. What’s more I think the main way we’re liable to do that is by going into space. The speediest manned vehicle in history was Apollo 10. It arrived at 25,000mph. Be that as it may to go in time we’ll need to go more than 2,000 times speedier. Also to do that we’d require a much greater ship, a sincerely huge machine. The boat might need to be huge enough to convey a gigantic measure of fuel, enough to quicken it to about the pace of light. Getting to simply underneath the grandiose pace cutoff might oblige six entire years at full power.
The introductory increasing speed might be tender in light of the fact that the boat might be so huge and substantial. In any case step by step it might get velocity and soon might be blanket gigantic separations. In one week it might have arrived at the external planets. Following two years it might achieve half-light speed and be far outside our earth’s planetary group. Two years after the fact it might be going at 90 for every penny of the rate of light. Around 30 trillion miles far from Earth, and 4 or 4.5 years after launch, the boat might start to go in time. For each hour of time on the boat, two might pass on Earth,a comparative circumstance to the spaceship that circled the monstrous dark gap.
After an additional two years of full push the boat might achieve its top speed, 99 percent of the velocity of light. At this velocity, and as stated by the figuring of researchers, a solitary day ready for an entire year of Earth time. Our boat might be sincerely flying into what’s to come.
 

To What Extent Does String Theory Present a Possibility of a Unified Theory of Quantum Gravity?

To what extent does String theory present a possibility of a Unified Theory of Quantum Gravity.

Abstract.

The report discusses the theoretical background of String Theory and makes a case for its resurgence in recent times to be a potential candidate for the Theory of Quantum gravity by addressing its former shortcomings and experimental methods.

Introduction

The objective of science has always been to make sense of the nature of reality. Scientists do this by following the Scientific Method. A fundamental part of the scientific method involves “observing” the phenomenon. This produces no issues as long as thing are easily seeable, but when science reached the borders of particle physics, this caused a big problem. Elementary particles are so small that they are “un-seeable”. Visible light just passes between particles. To solve this issue, scientists tried using light with higher energies and wavelengths per unit phase. However, such high energy interactions change the outcome of the result and hence provide no empirical understanding of how particles behave. (Roberston)

Point Particle

What is a particle? What does it look like? How do we record its behavior? To work their way around this problem scientists hypothesized the idea of the point particle. Scientists began hypothetically treating particles as points in 3-dimensional space. Comparing this particle to the vague results they would get from observing particles allowed the development of Quantum Field Theory which is the basis of all particle physics today and describes particle behavior fairly accurately. The principle that allowed scientists to make these calculations is called the Heisenberg Uncertainty Principle which claims that a particles position in space is inversely proportional to its momentum. (Roberston). In simpler words, it allowed us to get a general idea of particle interactions without having to accurately observe their behavior.

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However, since there is no way to measure things precisely in the Quantum world, the theory is not compatible with the theory of Gravity and General Relativity. GR requires accurate geometric measurements of matter in space time to work. When scientists tried to invent a carrier particle for gravity to make it work with QFT, the mathematics did not work. For some reason the point particle provided adequate accuracy to describe elementary particles but not for a carrier particle of gravity.

String Theory

To unify the two theories, scientists would have to develop a mechanics more complex than the point particle (Kurzgesagt – In a Nutshell). Hence, they hypothesized the existence of strings the size of plank scale, since topologically speaking, that is the second most complex structure following a point (Roberston). The hypothesis claimed that these strings served as the fundamental building blocks of reality instead of inherently differently behaving particles. It meant that everything was made up of very small strings of energy of specific frequency that would create these particles. Much like a vibration in a guitar string produces a sound, a vibration in an elementary string produces a particle. But most importantly, one of these vibrations would account for the particle carrier of Gravity, the graviton. This was revolutionary since string theory could describe interactions and behaviors of matter at both the quantum and cosmological scale. (Greene)

String theory immediately became a potential candidate for the unified Theory of Quantum Gravity which even Einstein could not put his finger on. However, as developments began, there was an obvious flaw in its workings.

String theory only works mathematically if we allow there to be 10 spatial dimensions. This is a huge problem since our universe only has 3 spatial dimensions. String Theorists tried to make calculations in 10 dimensions and then predict them in 3 dimensions, but the math was inconsistent.

This was essentially going to be the end of string theory even though it would accurately describe nature in a 10-dimensional universe. However, more recently, strides have been made in the field which might result in the extra 7 dimensions being a possible solution to the issue of string theory. This is called “Super-string Theory

Respected scientists such as IAS’ Dr. Edward Witten and Columbia University’s Dr. Briane Greene are devoted proponents of string theory.

The new model of String Theory embraces the 10 dimensions instead of trying to get rid of them. String Theory claims that there might actually be 10 dimensions in the world and that 7 of them are just extremely small to the point that they cannot be experienced by us. Take for example a wire. Its width might not be apparent to anyone but a very small ant on the wire. Similarly, it is entirely possible that we live in 10-dimensional space of which 7 are just not as apparent.

While this might just sound like an easy escape out of a situation, the 7 dimensions have actually much more to them.  

Experimentation

String Theory Hypothesizes that the extra 6 spatial dimensions are not directional like the 3 we experience but extremely small dimensions that fold over each other at the smallest levels. And that it is this folding and the different possible structures it creates that holds the key to understand some basic axioms of the model of Newtonian Physics. (Greene)

To make these calculations however, we need to know the shapes of those intertwined dimensions which we have no knowledge of. However by making calculations around a hypothetical set of potential shapes, if we manage to find those Newtonian axioms (Simon), it will be evidence of the theory being accurate since coincidences like that do not happen.

How was can we test this? One of the way to make calculations in particle physics is to use particle accelerators to collide two particles of known physical particles into each other at very high speeds. The debris and changes in energy pre and post collision allow us to make educated statements about the process.

If we can do the same experiment at very high speeds and can find that a certain amount of energy that breaks away from the collision corresponds to any of those Newtonian Axioms it will be evidence for not only the presence of the extra 6 dimensions but it will also predict their shape.

This will affirm String Theory in Solid Contention for a Theory of Quantum gravity if we can repeat the process for the properties of a Graviton, the carrier particle of Gravity.

Works Cited

Greene, Dr. Briane. “String Theory: Briane Greene.” TED-Ed, 9 August 2013. Video.

Kurzgesagt – In a Nutshell. “String Theory Explained- What is the true nature of reality.” Youtube, 1 March 2018. Video.

Roberston, O’Connor J J and E F. “A history of Quantum Mechanics.” 1966. Quantum Mechanics History. Document.

Simon, Herbert A. “Axioms of Newtonian Mechanics.” The London, Edinburgh and Dublin Philosophical (2010): 887-905. Document.