quantumnoobs-blog

[quantumnoobs-blog]

Stuckkk in the threee‼😨

Imagine. Being able to walk through everything, no cage to bind you. Being able to see through everything. And, you will be hailed as master surgeon* (conditions apply!) Well this may (read as: will) seem strange to you. This is as true as you are. But the question remains, HOW? Well for this we will have to travel across dimensions. O well ok. But how? First what is a dimension? Dimension is the minimum set of points needed to describe an objects location and\or location. Well this is the most complex definition of dimensions we can ever think of. So dimension is basically Cartesian coordinate system. So the first dimension is the x-axis second the y and third the z-axis.

So going on the nth dimension will be the nth axis. Therefore the number of dimensions equals no of axis of Cartesian co-ordinate system. So for first dimension you have a point. For second take infinitely many points and place them on left and right of each other and you get the 1st dimension, the x-axis. Now take this line and extend it on top and bottom at 90 degrees and voila! You get what we like to call the 2nd dimension (collectively both x - and y axes form the 2nd dimension). So the second dimensional plane is nothing but infinite number of 1 dimensional lines sacked in top and bottom directions. Now following this rule the third dimension is infinite no of 2-D planes attacked on top of each other making a third dimensional space. So following this the fourth dimension is infinite no of 3-D spaces. But in which direction? Where exactly is the fourth dimension and why can’t we see it? Hang on and let me walk you (like really slow!) through this! Get ready to get your minds blown. Now, the real discussion begins. Now, no nonsensical science fiction thoughts. Just PURE SCIENCE. Imagine. A land with no height just length and breadth i.e. basically a 2-D plane. This ‘magical’ land has no height so let’s call it FLATLAND. And the organisms living in it Flatlanders. Flatlanders have no height so they do not know and cannot even think of any axis or direction other than those available for them to access. As they altogether don’t exist in that z-axis.so, they cannot see or feel(unless some organism gives flatlander a visit from 3rd or higher dimension) or even think of anything in that dimension i.e. up and down directions for them (give this paragraph a thought, if you do not understand, give me a comment and I will get back to you). So imagine Mr. Square residing in the flatland. And Mr. Sphere residing in the 3rd dimension just above (or even below) our beloved Mr. Square. Mr. Sphere is unimaginably naughty and likes to do whatever he wants to regardless of the consequence. Now, following this behavior of his Mr. Sphere enters the flatland. What will happen? This:

As Mr. Sphere enters the flatland only points of contact of him will be visible to our now stunned Mr. Square. At first, there will be a point which will then enlarge into a circle with increasing diameters and the process will be then reversed, and the circle will convert into a point and vanish into thin air. So basically concluding, we (frankly I, and if you have followed then to only I) can say that Mr. Square is stuck in his universe, the Flatland, and Mr. Sphere is stuck in his! So as we progress, the nth dimensional creature is stuck in his and here Mr. Sphere’s role will be played by the (n+1)th dimensional creature. Where does this stop? Follow on and wait for my next installment in this series, and you will know the THEORETICAL limit of these dimensions. Hang on and we will meet soon! And yes if you want more info about that flatland I mentioned above, you can refer a book written beutifully by Edwin Abott titled Flatland.

-Ayaan Retiwala

[quantumnoobs-blog]

Empty space is not empty!!😀😀

In my previous article, I talked about Bigbang and how universe manifested itself into its current gigantic state, incase if you haven't read it please have a look at it. The link will be available at the end of this article.  Okay but what about the part that we didn't talk about??  What happened right at the beginning. This part can be defined as BigBang singularity. We don't know what happened at that point. Since at this point all our tools break down all physics based law break , time itself starts to wibble-wobble etc. To understand what happened at that point we need a theory that unifies Einstein's relativity and quantum mechanics, something countless scientists are still working on right now. There is another way of understanding why it's impossible to look back to the beginning using normal known laws of physics.So let's take an example: In the Zeno’s paradox of Achilles and the tortoise, Achilles is in a footrace with the tortoise. Achilles allows the tortoise a head start of 100 meters, for example. If we suppose that each racer starts running at some constant speed (one very fast and one very slow), then after some finite time, Achilles will have run 100 meters, bringing him to the tortoise's starting point. During this time, the tortoise has run a much shorter distance, say, 10 meters. It will then take Achilles some further time to run that distance, by which time the tortoise will have advanced farther; and then more time still to reach this third point, while the tortoise moves ahead. Thus, whenever Achilles reaches somewhere the tortoise has been, he still has farther to go. Therefore, because there are an infinite number of points Achilles must reach where the tortoise has already been, he can never overtake the tortoise. Just like the above-mentioned paradox, no matter how much we try to unravel the hidden mystery behind the beginning of the universe, we are just like Achilles trying to reach out to tortoise (the beginning of the universe) since tortoise or in this case the beginning of the universe had a head start it seems impossible to make contact.Okay enough with this let's talk about something more interesting.  Let's talk Quantum, a lot of scientists think that the first energy came to existence due to quantum fluctuations caused by virtual particles.So my topic for today is virtual particles so what are virtual particles?? and where do they come from?? Well in physics virtual particles are fluctuations in space-time which show the characteristic property of ordinary particles. Virtual particles are often popularly described as coming in pairs, a particle and antiparticle which can be of any kind. These pairs exist for an extremely short time, and then mutually annihilate almost immediately after they are created. The concept of virtual particles arises in quantum field theory an important part of the quantum mechanics (the world of the really small) where interactions between ordinary particles are described in terms of exchanges of virtual particles. They may not have the same mass as their twin real particle but they do conserve momentum and energy.  I want you to go ahead and think of an ideal vacuum with absolutely no matter in it and I have a question for you what is inside that vacuum??? Well, most of you would say that there is nothing and intuitively theirs nothing (an empty space) but what is actually profound is that empty space is not actually empty. It consists of a sea of virtual particles coming into reality and popping out of the reality. These particles explain a lot of physical phenomena that we are surrounded with; the  evaporation of black hole with time, the electron coming back to its initial lower state even after achieving higher stable state in an atom and etc Imagine an empty space as a series of points. You add energy by introducing particles or photons to one of these points it will oscillate back and forth with the same supplied energy like a harmonic motion affecting points of space around it. These oscillations in an empty space are called as quantum fluctuations and in this example, these series of points of energy constantly switching to different energy levels in a vacuum are called as vacuum energy. Now since we know Heisenberg's uncertainty principle states that the knowledge of two different but related quantities cannot be acquired at the same time. The other version of uncertainty principle states the same thing. The more the energy of a virtual particle, the less the time it sustains itself. So the longer the virtual particle stays in a real world, higher the chances are of it getting converted into a real particle. Isn’t it interesting that energy can exists in a vacuum rather than existing in a real particle? If virtual particles are not real particles then how do we know that they exist?? Quite a confusion right!! The best way to prove something is by mathematics and experiments. So let's have a look at something called as Quantum harmonic oscillator it's just a graph representing different energy levels where each energy level drop or rise requires a specific magnitude of quantum. The interesting thing to note down is the zero-point energy level in this diagram, all the particles that exist above this points are called as real particles while the particles below this point are called as virtual particles. This region of zero-point energy is filled with vacuum energy due to fluctuations in a field. Another experiment-based evidence that I would like to point out at is Casimir effect. If we take two uncharged metal plates put them around a micron apart and put them in a vacuum they will close together, Why?? For any photon to exist in between the two given plates it must at least complete half of its phase within the given distance. Since the space between the plates are just micron apart thus limiting the wavelength to completely fit in which causes the virtual photon between the plates to have to limited energy. Low energy means low pressure so the photon existing between the plates exhibits low pressure within the metal plates causing the pressure outside the plates to move in as the virtual particles existing outside the plates will have higher pressure since the particles outside have no limiting wavelength.  If all of this still doesn't make sense to you, it`s totally fine. You have all the time in life to make sense out of it. Let's talk about some interesting thought experiments..if you have a virtual particle pair with you and you decide to throw one of the particles from the pair inside a black hole crossing event horizon and let the other one escape. The particle that you let escape will eventually become a real particle, Quite interesting right!! But how??? Remember I said the virtual particles should annihilate themselves soon after they are created. In this case, the virtual particle pair didn't annihilate themselves, that's why the particle that escapes becomes a real particle. But what about the other particle that crossed the event horizon. Since it's difficult to retrieve any information about the particle after it crosses the event horizon. We don't know what happens to the other particle pair. Now the real question is how virtual particles get energy for the conversion. The answer is pretty simple Hawking radiation. Since we know black hole loses mass in the form of radiation and we know for a fact that radiation is a form of energy, that energy loss of black hole is used by the virtual particles and they convert themselves into real particles. Still, there are lots of ways you can convert them into real particles. 1) Unruh effect. 2) Boosting the pair apart using external force. 3) Vacuum decay. However, all particles have a finite lifetime, as they are created and eventually destroyed by some processes. As such, there is no absolute distinction between "real" and "virtual" particles. In practice, the lifetime of "ordinary" particles is far longer than the lifetime of the virtual particles that contribute to processes in particle physics, and as such the distinction is useful to make. We still don't know a lot about virtual particles. Their existence is a question of philosophy rather than science. What are your views on virtual particles?? Do let me know in the comments section. Till then Happy science-ing 😁😁 -Dilip Acharya

[quantumnoobs-blog]

Think, Rethink and Dethink🤔🤔

A lot of people often say that physics work on assumptions. So, I thought of doing a google search and this is what came up apparently, assumption means “a thing that is accepted as true or as certain to happen without proof”. So in the sense physics works without a proof on a thing that is bound to happen. It doesn’t make sense right, physicist often do a lot of thinking, rethinking and dethinking based on the evidence that completely relies on experiments. Anyways believing in it completely depends on you.

So I’m gonna start off my article with a story about a cute little puppy that I saw while traveling on my way back home from college. The puppy had a collar around its neck that was tied to a pole. Subsequently, a thought crosses my mind and I figured that the puppy’s situation is no different than us humans, how? The puppy could move around in a specific domain and hence wasn’t able to reach out to the unexplored territory. The same is with us we are surrounded by millions and millions of unexplored galaxies, constantly swirling around us, we know that they do exist but our inability to venture the laws of physics is holding us back from exploring the unknown.

The current speed at which our universe is expanding is roughly estimated at 72.8 kilometers per second per mega-parsec ( one parsec equals 3.082×10^16 ) which will double in another 9.8 billion years. The important thing to note down is that the expansion is not steady, it’s accelerating and its going on for 13.82 +/- 0.12 billion years now and since the expansion rate is increasing and the basic interpretations say that the speed in which the distance between the galaxies is increasing faster than the speed of light so even if you somehow are able to achieve the speed of light (which is not yet possible) you still don’t reach out to the unknown. It’s the same as the puppy trying to reach out for the unexplored territory that I mentioned earlier before.

But why is the universe expanding??How did the universe expand into its current state?? Questions!! Questions !! In 1965, George Lemaitre first noted that the universe is expanding and might be traced back in time to an originating single point. At that time the whole of the scientific community was divided into two one in favor of steady state theory and others in favor of Big bang theory. Einstein’s theory of relativity gave us a better understanding and Edwin Hubble discovered that the galaxies are moving apart from each other by observing redshifts. In 1965 we were able to discover cosmic background radiation (CMBR), a relic of the early universe. Since Big bang predicted about its existence even before its discovery and since it was able to explain about the abundance of the lighter elements, large structure and Hubble’s law, Big bang`s model of the universe was accepted worldwide. Before I begin with the explanation part, I want you to imagine trying to squeeze space-time to a point where our known observable, as well as the unobservable universe, was infinitesimally small, space and time these two entities had no meaning they were one and the same. Energy and matter were not just theoretically equivalent they were practically the same thing. All the fundamental forces that we know now were once a single unified force. That point is known as big bang singularity. Well, some agree that the universe expanded from a single point and some don’t. We still have no knowledge of that point since all the physics based law breaks down at that point, Time starts wobbling and etc. 

So let`s explore what we know, In 1949 English astronomer Fred Hoyle coined the term “Big Bang” during a  BBC radio broadcast. And since then a lot of people have taken the term big bang in a wrong sense sorry to burst your bubbles starters, but Big bang is not what you think it is, it isn’t an explosion its pure expansion of space into itself which started off with the high temperature, high density and as the universe expanded the temperature cooled down forming subsequent particles and then atoms, the amount of matter spread out in the universe creating homogeneity and isotropy of space. Because the name is so catchy nobody tried to correct it. Another contradiction to the meaningless term big bang is that it uses a term ‘bang’ and the meaning of the term is ’ sharp noise ’ since there existed no medium for sound to travel there would have been no noise to listen to. Anyways, let’s understand the history of the universe with big bang perspective. 

Approximately 10^-37 seconds into the expansion, a phase transition took place that we call as cosmic inflation, during which the universe expanded exponentially. In this transition, a football-sized universe was given birth from almost nothingness. In this hot dense environment, energy manifested itself at exactly 10^-32 seconds into the expansion, pairs of quarks were created from gluons which started multiplying themselves into huge numbers. After approximately 10^-9 seconds of expansion, all the fundamental laws of nature started to function and gradually the density and the temperature parameters dropped down exponentially. After 10^-6 seconds of the big bang, quarks and gluons combined together to form baryons such as protons and neutrons. An unknown phenomenon called baryogenesis which broke the law of conservation of baryonic number ultimately causing the abundance of baryon over antibaryon. Somewhere around this point of time matter won over antimatter, which explains the abundance of matter over antimatter for almost one billion and one matter there existed one billion antimatter. Now the temperature of the universe was not high enough to create more protons and antiprotons so the series of mass annihilation begun leaving just one in every 10^10 of the original proton and neutron and none of the antiprotons. The same happened with electron and positron after about one second to expansion. A few minutes into the expansion, when the temperature was about a billion Kelvin and the density was about that of air, neutrons combined with protons to form the universe’s deuterium and helium nuclei in a process called Big Bang nucleosynthesis. Most protons remained uncombined as hydrogen nuclei. After about 379,000 years the electrons and nuclei combined into atoms (mostly hydrogen); hence the radiation decoupled from matter and continued through space largely unimpeded. This relic radiation is known as the cosmic microwave background radiation. This answers a lot of questions that is constantly being asked by the masses the one that I can remember of goes by…If we are to look into space searching for a galaxy far far away…it is said we can look into its past because the light from the source takes the time to reach us. Now by just looking into space why can’t we observe big bang….the answer is pretty simple the method that is used to observe the past is based on cosmic microwave background radiation detection to make it more simple the first light that was emitted by our universe (photon emission) and since I mentioned that the first radiation was formed after 379k years of expansion so it is quite impossible and unachievable. But there is still small hope left, the first neutrinos were formed way early in the universe, but neutrinos don’t interact with normal matter if we somehow succeed in doing that….we get one step closer to looking into the unknown past.

But this leaves us with lots of unanswered questions How did big bang start?? Was there a beginning to this universe?? We don’t know, maybe we never will. What we do know as of now is that our universe speaks for uni means one, the verse means song and we all have a part to play in this song. So keep learning, keep growing and Happy science-ing😁😁

- Dilip Acharya

[quantumnoobs-blog]

Energy is the new Mass! :) :)

When we are in the midst of the battle we often forget to comprehend small, but valuable details. A great example is 'unsinkable' Titanic everyone was so much indulged in preparing it, but at the time of journey the binoculars that could have been used for lookouts on the night of the collision were locked up aboard the ship — and the key was held by David Blair, an officer who was bumped from the crew before the ship's departure, icebergs that hit the ship might have been spotted earlier if the binoculars were in use. The lack of information and inaccuracy in communication always lead to a loss.

Ever since we were children, started studying and understanding physics our teachers or someone would have at least once said; "Mass can be converted into Energy" and we even believed it and it`s still glued to our memory to some extent. This statement reminds me of the same titanic story that I mentioned above. This statement is completely wrong and it doesn`t make sense. In physics, mass is a property of a physical body. It is the measure of an object's resistance to acceleration (a change in its state of motion) when a net force is applied or to speak in terms of energy "Mass is the characteristic property of energy"(In special relativity at higher velocity).The famous einstein`s equation E=mc^2 originally written as m=E/c^2 in his 1905 published paper. The Einstein's famous equation was not really explaining energy but it was trying to explain to us how to think about what mass is. Even if two objects are made up of identical constituents those objects will not, in general, have equal masses. The object that is made up of its constituent sum of masses is not just the sum of those masses. Instead, the total mass of the composite object also depends on how its constituent parts are oriented and how they move within the bigger object.

I`ll try to explain all those stuff that is written and would try to clear things up a little bit using examples:

If you take a winding car and measure its mass using a weighing machine (consider it a highly sensitive and accurate detailing machine) you get its actual mass say the machine displays 50 units ,then if you take the same winding car and wind it a little bit and when you try to measure its weight during its state of motion you observe that its mass changed to 50.00000000000000001 units. Yes! indeed it weighs more than the actual weight of the car. The reason is the toy car is moving so it has some kinetic energy there are also wound up springs in the moving car that adds up to its potential energy and there is a little bit of frictional energy also between the surface and the moving car that heats it up, which causes the atoms in the car to jiggle up a little bit .That`s thermal energy or equivalently randomized kinetic energy on a microscopic level. The extra mass is so tiny that it measures nearly one by a billionth of a billionth the mass of the car, that is why most of us incorrectly believed that mass is the amount of matter in an object, but in reality, energy also contributes to the total mass of an object.

Another famous example that most of us use is Sun, it acts as the source of light. The light that sun emits carry energy, sun`s energy contributes to the total mass of the sun hence it results in the reduction of mass. On an average sun loses 4 billion kgs/sec which is 1/10^21 kg of its total mass and that`s just 0.7% of the sun`s 10 billion years of life span. Some of you might be still thinking that the sun converts mass into energy it`s quite wrong. Sun doesn`t convert mass into energy, it is the energy that we calculate in terms of mass it's just we didn't realize that it was never the mass, it was energy from the very beginning. Even the protons and neutrons gain mass based on Einstein's E=mc2. As we know protons and neutrons are made up of quarks these quarks exhibit quark potential energy technically speaking gluons that glue all the quarks together via strong interaction force. This equation is quite incomplete the actual equation is E^2=(mc^2)^2 +(pc)^2

where, E=Energy m=mass c=speed of light p=momentum

E=mc^2 works when it`s a rest mass by that I mean velocity or momentum of the mass should be zero.

I hope u understood the whole point of this topic. At last, I would like to say "Time runs faster when u enjoy it, so enjoy it". Happy science-ing 😀

-Dilip Acharya