Stephen Hawking, Physicist Who Makes Black Holes So Glow

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Recently, March 14, 2018, Stephen Hawking’s name has become more resonant than ever before. The news of the death of the most famous physicist after Albert Einstein is filled the virtual world, drove across the vast ocean, to our country Indonesia. Stephen Hawking rested forever at the age of 76.

Stephen Hawking is often dubbed the smartest living human being. There is little pride in our minds because it is lucky to be able to live as a great scientist. But now that sense of pride has gone, along with the last breath that blows from this physicist.

Stephen Hawking, age close to 76 years (January 8, 1942 – March 14, 2018)

One of Stephen Hawking’s great contributions to physics is his theory of black holes . Black hole is a very massive object so no one can escape from the pull of gravity.

Initially black holes are only considered as mathematical objects born of the general theory of relativity only. But now we know that the black hole really exists in the real world. [1]

What is Stephen Hawking’s contribution to the theory of black holes? Consider the following explanation.

The Stained Space Is Not Really Hampa

Our reasoning is shaped by experience. At first we thought that heavy objects fall faster than light objects. This is because in everyday life we ​​do see it that way. But after we look more closely it does not. Heavy objects and light objects fall together when air resistance is removed. This is the reason why the theory of relativity and quantum theory is difficult to digest by reason. In everyday life we ​​have never dealt with super-fast objects or super-small objects. That’s why we should not be too confident with our common sense .

The law of conservation of energy is a very logical law, in accordance with our daily reason. It is impossible for matter to appear suddenly from the void. But it turns out two plus two is not always equal to four. Quantum theory has modified the law of conservation of energy through a principle whose name is Heisenberg’s uncertainty. Material may suddenly emerge from the absence provided that it vanishes immediately. The consequence of this is very spectacular. Heisenberg’s uncertainty principle gives us a new understanding of what voidness is.

What comes to mind when we hear the word “hollow”? Our reason describes emptiness as emptiness, nothingness, dark black, without anything there. But it turns out that quantum theory says something else. The vacuum is not really empty. The vacuum was full of activity. Couple particles and anti-particles suddenly appear then meet again and mutually eliminate. Appears to disappear, reappear, disappear again, and so on. According to quantum theory, vacuum is a very crowded place. [2]  This quantum theory is used by Hawking to describe black holes.

Theory of General Relativity vs. Quantum Theory

Today almost everything that exists in the heavens and on earth can be explained by two major theories of physics, the theory of general relativity and quantum theory. The general theory of relativity is able to explain massive objects such as stars, galaxies, and the universe. Meanwhile, quantum theory is able to explain small objects such as atoms, protons, and electrons.

Normally large mass objects must be large in size so we do not need to review them with these two theories at once. But there are two places where small objects have a very large mass at the center of the black hole and at the beginning of the universe.

To find out what happens at the center of the black hole as well as at the beginning of the universe, we need to unite the general theory of relativity with quantum theory. This theory of unification is the dream of Stephen Hawking, Theory of Everything .

But it turns out to unite the two (the theory of general relativity and quantum theory) is not easy. Until now we still do not have Theory of Everything so we still can not analyze what happened at the center of the black hole and at the beginning of the universe.

Stephen Hawking has not been able to figure out what’s going on in the center of a black hole because he has not succeeded in composing Theory of Everything . But he has made the first step to get there. Before approaching the center of the black hole, it is better to grope the surface first.

Researching the surface of a black hole does not need to use Theory of everything in its actual version because the gravity there is not as strong as gravity at the center of the black hole. Simply use quantum theory but in a curved spacetime background . [3]

Hawking Radiation

What happens when Stephen Hawking sees the surface of a black hole using quantum theory? This is where the revolution takes place. Hawking sees a pair of particles and anti-particles that appear on the horizon of a black hole. Black hole has a horizon or a safe distance. Any object that includes light when it has crossed the horizon will not get out again. That’s why the black hole is black, because no light can come out of it.

Hawking Radiation

Some of the particle and anti-particle pairs that appear on this horizon will not be able to meet again to cancel each other out. As a result, one particle enters the black hole and the other is released as radiation. Particles that enter the black hole have a negative mass that will reduce the mass of black holes.

From the outside, black holes appear to shrink while emitting radiation. Radiation is then known by the name of Hawking Radiation . It is a revolution because the former black hole is known as an object that does not want to remove anything that has been swallowed. But Hawking said that the black hole turned out to emit radiation alias “shine”. [4]


[1] Science Channel. 2014. Through the wormhole – The riddle of black hole . accessed March 14, 2018

[2] Krauss, Lawrence. 2012. A Universe from Nothing . USA: Free Press

[3] Carroll, S. (2004). Spacetime and Geometry, An Introduction to General Relativity Chicago: Addison Wesley

[4] Muon Ray. 2015. Stephen Hawking Lecture – How to Escape Out of a Black Hole. accessed March 14, 2018

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What's a Worm Hole (Wormhole)? Theories, facts, and expectations about the Wormhole

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The universe is very broad. There are about 10 trillion galaxies in the universe, each galaksinya contains about 100 billion stars [1]. Amazing how can imagine the abundance of beautiful planets out there. Billions of planets floating in the darkness waiting for us to come there, making them the second place to live as if the Earth was gone not left. Either because it was hit by a meteor or destroyed by humans who love to dispute.

I wish we could ignore all the differences that exist among us and to work together on behalf of humanity, finding a new planet habitable is not difficult. It is more difficult than finding planets is how to go there. The distance is a problem. Gliese 581 d, Earth-like planet that is closest to our tatasurya the distance is already more than 20 light years [2]. This means that it takes more than 20 years for light to get to there. Moreover, our aircraft that its velocity is still very much below the speed of light, it would take much longer.

A hope: the worm Hole (wormhole)

Nature gives us hope. According to one of the named natural law theory of general relativity, there is an object that can serve as a tunnel intergalaktik. The tunnel named wormhole (wormhole). Although the name of this object but the wormhole has nothing to do with a hole or a worm. Wormhole is a structure in space-time that can link two distant regions in the universe. By using a wormhole, a journey that normally takes many thousands of light years away can be reached in a short time.

Wormhole is different from a black hole. The black hole is indeed absorb all the material and waves but the material and this wave not spewed out by a black hole somewhere in the universe. Objects that already goes into a black hole will be torn apart the atomic level and merges with the heart of a black hole. Meanwhile, things that went into the wormhole will pop up again somewhere in the universe.

The term wormhole is derived from the Apple analogy. Our universe is likened to the surface of an Apple and we likened as an Ant who can only walk on the surface of the apples.

Wormhole on apples

Suppose we want to go from one point to another. We certainly must be running in a curved path. But if we become a worm, then we could take Apple to produce a shorter new road. The ants eventually could use the road made by this worm in order to get to your destination faster. Scientists call this shortcut with the wormhole.

The concept of wormhole born accidentally in the hands of Einstein. Wormhole was not originally considered a shortcut connecting two distant places in the universe. In 1935, Einstein, along with Nathan Rosen attempt formulated the theory of fundamental particles (such as electrons) using the theory of general relativity. Einstein wanted to make his theory as a Theory of Everything, not only explains the theory of space and time but also everything that is in it, which of course is composed of fundamental particles. With complex mathematical analysis and complex, so the object known as the Einstein-Rosen bridge (Einstein-Rosen bridge). Unfortunately the attempt was unsuccessful. Einstein However, the remnants of this Einstein work did not vanish entirely. Einstein-Rosen bridge thus became the object of study of its own and now we call it with the name of the wormhole. [4].

False Hope?

In 1962 we are a little disappointed because the wormhole made it seems is just another false hope for intergalaktik travel dreams. In it, Fuller and Wheeler did further investigation and conclusion that the wormhole is apparently very unstable so there may be bypassed.

If the hole the worm appeared. then in a very short time he will close again, turns into a black hole. So before we got in, wormhole was closed again. Even if we tried to go as fast as we could, we would just be wedged in the mouth of the wormhole and disappear in the singularity (the heart of a black hole). [5] the dynamics of wormhole

In order that the wormhole is not shut down again, we need to hold it in a manner give him negative material. Negative material is a material which has properties of anti-gravity. Negative material is not mutually attract each other but refused. The usual Apple will fall down if we're throwing apples but negative thus will continue to rise to the top. We've never seen this kind of object. I wish we could find a material negative then the wormhole can be bypassed. [6]

Negative material may indeed be making the wormhole can be skipped, but the only wormhole that already exist from the early IE since the birth of the universe. To create a new wormhole, we should be dealing with a bigger problem. If we want to create a shortcut from Earth to other galaxies then we should "tear up" the space and dial back (in mathematical language is changing the topology).

General theory of relativity did say that that space is flexible. Spaces can be curved, twisting, and can be wavy. But the space will not be torn down [7]. Thus, the theory of general relativity allow the wormhole to exist but does not allow for the wormhole is created.

There is still hope

History of the wormhole is the history of hope and disappointment. After being disappointed because the wormhole takes negative material to be bypassed as well as requiring a tear in space in order to be established, there is a glimmer of hope of quantum theory.

Quantum theory is opposed to the theory of general relativity. Theory of general relativity explains the objects are very large while quantum theory describes the objects are very small. The opposite turned out to be two theories could work together to solve a problem.

We did a negative material has never seen in everyday life, but the quantum theory States that negative material that exists. According to the quantum theory too, the Rip-Rips in space it is common in microscopic scale.

So that there is a wormhole can be formed, but in a very small size [7]. We need to do "is simply" blow up the wormhole mini so that its size becomes large. Of course this is far from the reach of our current technology. In addition, we also do not yet know whether quantum theory allows us to make quite a lot of negative material [8]. Here is a video about how scientists make the wormhole in the laboratory.

Because of these difficulties, coupled with some other difficulties, many physicists were no longer hope to the wormhole. However, that does not mean there is no hope for interstellar travel. There is still hope other than such a wormhole warp drive. One thing is for sure, if we mutually destroy each other with war and hatred in that moment that we had no hope at all.



[1] Howell, Elizabeth. 2017. accessed 21 February 2018 [2] Stphen Hawking. 2015. Into The Universe With Stephen Hawking The Story of Everything. Accessed February 21, 2018. [3] a. Einstein and n. Rosen. 1935. The particle problem in the general theory of relativity. Phys. Rev. 48 [4] 73-77, Collas, p., Klein, d. & 2011. Embeddings and time evolution of the Schwarzschild wormhole. arXiv: 1107.4871 v2 [5] Fuller, r. d., & Wheeler, j. a. 1962. Causality and Multiply-Connected Space-Time. Physical Review, 919. [6] Morris, m. s., & Thorne, k. s. 1988. Wormhole in spacetime and their use for interstellar travel: A tool for teaching general relativity. American Journal of Physics, Volume 56. [7] Tia Ghose. 2017. Magnetic Wormhole Created in Lab. Accessed February 23, 2018. [8] Quantum Laser Pointer. 2016. The Elegant Universe – String Theory – Brian Greene – Documentary. accessed February 21, 2018.

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Get to know the CPA on the packaging of Food Products and their impact on Health

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Have you ever heard the term CPA? Has thought of the chemical components that inadvertently we consume? Even our pets come into consumption.

Bisphenol A or BPA with abbreviated became one of the major research topics in recent years because it is well known that BPA has estrogenic activity. Oestrogenic activity is activity resembles the activity of in vitro and/or in vivo of natural estrogen. CPA is a component of the resin contained in almost all cans good for human food or animal food (petfood). BPA is a chemical compound produced by the condensation of acetone synthesis with two equivalents of phenol. These compounds are used to produce a particular plastic packaging and epoxy resin (Beynen 2017), and is often found on food packaging and beverage cans. A survey conducted recently by Liao and Kannan Monday (2013, 2014) in the United States and China mentioned that food cans contain BPA usually with higher concentrations compared to food packaged in glass, paper or plastic (Cunha et al. 2017).

BPA is dangerous if taken as it can affect hormone regulatory process. Small amounts of BPA consumption would increase hormonal disease progression (Beynen 2017). Hormonal diseases have symptoms that are quite complex because it directly influences the physiological functions of the body or some other. This is pretty much a hormonal diseases related to disorders of endocrine glands function. The last few years, it is known that there is a relationship between some endocrine disease with exposure to BPA in humans. BPA can cause decreased ovarian response and the success of in vitro fertilization. Exposure to BPA can also lower sperm quality in men and the occurrence of changes in the female reproductive system. In children, BPA can damage the development of the nervous system. Further note that the CPA is also associated with metabolime disease such as type 2 diabetes, cardiovascular, liver function changes, obesity, albuminaria, and oxidative stress (Cunha et al. 2017). CPA is also known to negatively affect pets who eat canned food. The results of the latest studies mention that the CPA proved to be thyroid related diseases (hyperthyroidism) in cats (Beynen 2017).

CPA is considered harmful to health because there is a possible illicit compounds that migrate from the inside coating of packaging to the food product itself due to heat treatment.

Currently several companies already require suppliers of canning Tin to not use BPA in cans that their production. Consumers began to understand the dangers of BPA so that some consumers have added BPA-free specifications on products they have requested.  The European Commission has set a tolerable daily intake (TDI) for BPA i.e. 4 µ g/kg body weight (EFSA 2015), while the maximum daily amount that can be accepted by the U.S. Environmental Protection Agency are 50 µ g/kg (FDA 2008). The EU Commission also set a limit on the amount of BPA that are allowed to migrate from packaging into food, commonly known by the migration limit. The migration limit of 0.6 mg/kg (CR EU 2011).


  • Beynen a. 2017. BPA in canned petfood. Creature Companion (2017): 33-34.
  • [CR EU 2011] Commission Regulation (EU) No. 10/2011 of 14 January 2011 on plastic materials and articles intended to come into contact with food.
  • Cunha S, RN, Fernandes ALves JO, Casal S, Marques a. 2017. First approach to assess the bioaccessibility of bisphenol A in canned seafood. Food Chemistry 232 (2017): 501-507.
  • CEF Panel of EFSA (EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids) (2015). Scientific Opinion on the risks to public health related to the presence of bisphenol A (BPA) in foodstuffs: Executive summary. EFSA Journal, 13 (3978), 23.
  • 2008-FDA Draft assessment of bisphenol A for use in food contact applications.
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