Chapter 248 (1/2)

Solution of a class of linear stochastic differential equations?

Cheng Nuo points to the documents sent by Wang Ji and studies them carefully.

The solution of a class of linear stochastic equations has been learned in the freshman course of mathematics department.

If Cheng Nuo remembers well, for differential equations, we should use the constant variation method to solve them.

This is the most commonly used and generally accepted as a relatively simple method for solving differential equations.

The constant variation method, in short, is to find the solution of the homogeneous differential equation corresponding to the differential equation, and then obtain the explicit solution of the equation by changing the constant.

For example, the stochastic differential equation D ￡ = f (T) ￡ DT + C (T) DB is rewritten as D ￡ - f (L) ￡ DL = C (T) dB, and its corresponding homogeneous linear stochastic differential equation is Then we imitate the appropriate factor method in the ordinary differential equation Finally, ￡ = （“”ω“”)(●′-`●)。

(I really can't type it!)

Here's the point!

In this paper, Wang Ji proposed another solution of linear stochastic equation besides the constant variation method.

Another solution is simpler than the constant variation method which we have been using all the time.

It can be said that if this solution is really proved to be available, it will definitely produce a small-scale vibration in the field of differentiation.

Not to mention the SCI journals of mathematics zone 2, even the top journals of mathematics Division 1, will definitely attach importance to Wang Ji's paper.

But it's a pity.

The editors of the journal pointed out that there was a major logical error in Wang Ji's paper.

Whether his solution is really practical is still in the middle.

Cheng Nuo drags the mouse, continues to look down.

The simple solution proposed by Wang Ji is as follows:

in the first step, the solution of pseudo homogeneous differential equation is obtained.

The second step is to change the constants of solutions of pseudo homogeneous differential equations.

In the third part, it is brought to the original equation to verify the solution.

On the surface, it is really simpler than the constant variation method.

The content of the following paper is that Wang Ji demonstrates the feasibility of this solution through the formula.

Cheng Nuo glanced roughly.

Generally speaking, the idea of Wang Ji's paper is very clear.

From putting forward the conjecture, to proving the conjecture, and then to explaining the advantages of this solution compared with the constant variation method.

But

After a simple scan from the beginning to the end, Cheng Nuo finally understood why Wang Ji's paper had been knocked back and overhauled by SCI journals.

In the third process formula of the later demonstration stage, there is a serious logic error!

I don't know the true face of Lushan Mountain, but I live in this mountain!

As the author of this paper, Wang Jian is hard to find his own mistakes. On the contrary, Cheng Nuo, a bystander, only scanned the paper from the beginning to the end and found the problems.

QQ side, Wang Ji does not seem to think that Cheng Nuo can find the mistakes in his paper.

Although he had to admit Cheng Nuo's great talent in mathematics.

However, with Cheng Nuo's current knowledge reserve, it is still uncertain whether he can understand his thesis.

Wang Ji yawned and sent a message to Cheng Nuo, ”OK, Cheng Nuo, I'll go to bed first. I'll take some time to look at your research results tomorrow, and I'll start my part. ”

Wang Gen basically plans to turn off the computer and go to bed. But when he looks up, he finds that Cheng Nuo has returned a message to him, ”senior student, wait a minute. I feel like Know where you've made a mistake. ”

What?!

Seeing this message, Wang Jiji woke up half asleep.

This is Really?

He has just published his paper in less than five minutes. It is a tight time to have a rough look at it from the beginning to the end. However, Cheng Nuo told him that he had found the major logical error mentioned by the editor of SCI journal.

How could it be!

Wang Ji couldn't wait to type in the past, ”what you said is true?”

Cheng Nuo: ”of course.”