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The speed of light being a constant sounds like a simple statement. But there is more to it, quite a bit more. Let’s look at what this constancy really means. Pada pandangan pertama, it says that if you are standing somewhere, and there is a ray of light going from your right to left, it has a speed c. And another ray of light going from left to right also has a speed c. Setakat ini, so good. Now let’s say you are in a rocket ship, seperti yang ditunjukkan dalam rajah di bawah, moving from right to left.

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Teori Khas Relativiti

Apabila kita mendengar tentang Einstein dan kerelatifan khas (atau teori khas relativiti, untuk menggunakan nama sebenar), kita fikir yang terkenal E = mc^2 persamaan, dan perkara-perkara pelik seperti paradoks kembar. Walaupun perkara-perkara adalah benar dan penting, masalah SR cuba untuk menyelesaikan adalah salah sama sekali berbeza. Ia adalah satu usaha untuk mempertahankan prinsip asas dalam fizik.
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Quantum Field Theory

In this post on Quantum Mechanics (QM), we will go a bit beyond it and touch upon Quantum Field Theory – the way it is used in particle physics. In the last couple of posts, I outlined a philosophical introduction to QM, as well as its historical origin – how it came about as an ad-hoc explanation of the blackbody radiation, and a brilliant description of the photoelectric effect.
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Mekanik Kuantum

Mekanik Kuantum (QM) is the physics of small things. How do they behave and how do they interact with each other? Conspicuously absent from this framework of QM is why. Why small things do what they do is a question QM leaves alone. Dan, if you are to make any headway into this subject, your best bet is to curb your urge to ask why. Nature is what she is. Our job is to understand the rules by which she plays the game of reality, and do our best to make use of those rules to our advantage in experiments and technologies. Ours is not to reason why. Really.

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Classical Physics

The main difficulty in describing particle physics to general public is the fact that it is built on modern physics. Even if you are physics aficionado and did extremely well in your high school physics, what you have learned and loved is classical physics. The difference between classical physics and modern physics is not just more physics, but a completely new way of looking at the reality around us.
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reduksionisme

Dalam segala usaha saintifik kami, kita menggunakan teknik peringkat tinggi sama untuk memahami dan mengkaji perkara. Teknik yang paling biasa adalah reduksionisme. Ia adalah berdasarkan kepada kepercayaan bahawa tingkah laku, ciri-ciri dan struktur objek yang besar dan kompleks boleh difahami dari segi pengundi mereka lebih mudah. Dalam erti kata lain, kita cuba untuk memahami keseluruhan (the universe, misalnya) dari segi yang lebih kecil, juzuk dikurangkan (seperti zarah).

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Zarah dan Interaksi

Baru-baru ini, Saya memberi penerangan mengenai zarah dan interaksi dengan rakan-rakan anak perempuan saya yang merancang untuk perjalanan ke Desy, Jerman dan mahu mempunyai idea tentang apa yang ia adalah semua tentang. Ceramah pertama saya seperti ini, Saya agak gementar kerana saya tidak tahu apa tahap, dan latar belakang, Saya perlu menambat ceramah di. Saya tidak mahu membuat ia terlalu asas, yang saya fikir akan menjadi satu pembaziran masa. Juga aku tidak mahu menjadikan ia terlalu teknikal, yang juga akan menjadikan ia tidak berguna dengan cara yang berbeza.

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Sensory and Physical Worlds

Animals have different sensory capabilities compared to us humans. Cats, misalnya, can hear up to 60kHz, while the highest note we have ever heard was about 20kHz. Rupa-rupanya, we could hear that high a note only in our childhood. Jadi, if we are trying to pull a fast one on a cat with the best hifi multi-channel, Dolby-whatever recording of a mouse, we will fail pathetically. It won’t be fooled because it lives in a different sensory world, while sharing the same physical world as ours. There is a humongous difference between the sensory and physical worlds.

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