عملگرهای جبر رابطه ای

عملگرهای معمولی: اجتماع، اشتراک، تفاضل، ضرب کارتزین

عملگرهای خاص: گزینش(تحدید)، پرتو، پیوند، تقسیم

Qubit

http://asiac.ir/?p=1382

قانون جابجایی ویلهلم وین فیزیکدان آلمانی:

 

حاصلضرب دمای مطلق یک جسم و طول موج تابش شده از آن یک مقدار ثابت است.

λ_max × T = C مقدار C در این فرمول 0.002897mK می باشد.

 

این موارد در فیزیک کلاسیک قابل توضیح نبودند که منجر به ایجاد فیزیک کوانتوم شد:

1. تابش جسم سیاه
2. پدیده فتو الکتریک
3. اثر کامپتون

Ultraviolet catastrophe

In the beginning there was continuous flow, and then Max Planck came along and proposed quantization. Quantization basically just means, that instead of being continuous, things such as EM radiation, can only exist in multiples of certain values. It’s a little bit like having a tube of smarties. The whole tube represents a beam of light. Inside it you have the smarties. You can split the tube, so you can have less smarties in there, or you can get another tube and have smarties, but you have to have a whole number of smarties, because they can’t be split (if anyone e-mails me suggesting I squash/crush/split a smartie, I will hunt them down and make them pay!).

Planck came to this conclusion when working on the “Ultraviolet Catastrophe”. According to classical electromagnetism, the number of ways an electromagnetic wave can vibrate a in a 3-dimensional cavity, per unit frequency, is proportional to the square of the frequency. This means that the power you would get out per unit frequency should follow the Rayleigh-Jeans law, which means that the power would be proportional to the frequency squared. So if you put the frequency up higher and higher the power would be unlimited. Planck said that electromagnetic energy did not follow the classical description. He said that it could only be emitted in discrete packets of energy proportional to the frequency

oblivious

Us : /əˈblɪviəs/   Uk : /əˈblɪvɪəs/

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(معمولا با: of یا to) بی خبر (از)، بی اعتنا (به)، فراموشکار، بی توجه

Cursor

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