University of Cambridge

Mistakes in conversational "artificial intelligence"

H. K. D. H. Bhadeshia

There follows experiments in which I used sentences from the introductory chapter of Steels: Bhadeshia and Honeycombe to check what the conversational "artificial intelligence" machines come up with. Each section begins with a sentence in italics, from the book, followed by the response.


Iron is created in the stars, which at first fuel themselves through the fusion of hydrogen and helium

Yes, that's right. Stars are giant balls of gas that are held together by gravity. The pressure and temperature at the core of a star are so high that hydrogen atoms can fuse together to create helium atoms. This process releases a tremendous amount of energy, which keeps the star from collapsing under its own gravity.

The star will continue to fuse hydrogen into helium until the hydrogen supply in the core is exhausted. At this point, the star will start to fuse helium into heavier elements, such as carbon and oxygen. This process will continue until the star reaches a point where it can no longer fuse any heavier elements. At this point, the star will collapse in on itself and explode in a supernova.

The supernova explosion will create a shockwave that will blast the heavier elements that were created in the star's core out into space. These elements will then be incorporated into new stars and planets. So, in a sense, we are all made of stardust!

Gold standard

such is the success of iron, that steel forms the 'gold standard' against which emerging materials or supreme acts of endeavour are compared.

That's a very interesting way to think about it. Iron is such a versatile and durable material that it has become the go-to material for many applications. It is used in everything from buildings and bridges to cars and appliances. Steel, which is an alloy of iron and carbon, is even stronger and more durable than iron, making it the perfect material for use in high-stress environments.

It is no wonder, then, that steel is often used as the benchmark against which other materials are compared. If a new material is said to be "as strong as steel," that is a high compliment indeed. And if someone is said to have "performed a feat of steel," that is a sign that they have accomplished something truly remarkable.

So, while iron may not be the most glamorous material on the planet, it is certainly one of the most important. It is a material that has shaped our world in countless ways, and it will continue to do so for many years to come.


One reason for the overwhelming dominance of steels is the endless variety of microstructures and properties that can be generated by solid-state transformation and processing.

That's right. Steel is an alloy of iron and carbon, and the properties of steel can be varied by changing the amount of carbon, as well as the other elements that are added to the alloy. The microstructure of steel can also be changed by heat treatment, which can alter the way that the carbon atoms are distributed in the steel. This gives steelmakers a great deal of flexibility in designing steels with the desired properties for specific applications.

For example, low-carbon steels are relatively soft and ductile, making them well-suited for applications where formability is important. High-carbon steels, on the other hand, are much harder and stronger, making them ideal for applications where wear resistance is critical. And stainless steels, which contain chromium and other elements that resist corrosion, are used in a wide range of applications where durability is essential.

The endless variety of microstructures and properties that can be generated by solid-state transformation and processing is one of the key reasons why steel is such a versatile and widely used material.


For comparison purposes the breaking strength of a very small carbon nanotube has been measured to be about 130,000 MPa; this number is so astonishing that it has led to misleading statements about their potential in structural applications.

That's a very interesting point. Carbon nanotubes are indeed incredibly strong, and their potential applications in structural engineering are vast. However, it's important to remember that the breaking strength of a carbon nanotube is measured in ideal conditions, and that the strength of a real-world structure made from carbon nanotubes would be much lower. This is because carbon nanotubes are very difficult to manufacture and assemble, and they are also susceptible to damage from environmental factors.

Despite these challenges, carbon nanotubes are still a very promising material for structural engineering. With further research and development, it is likely that carbon nanotubes will one day be used to build strong, lightweight structures that are resistant to damage.

In addition, the breaking strength of a carbon nanotube is not the only factor that determines its potential in structural applications. The stiffness of a carbon nanotube is also important, as is its ability to withstand fatigue. Carbon nanotubes are also susceptible to creep, which is the slow deformation of a material under constant load. These factors must all be considered when assessing the potential of carbon nanotubes for structural applications.


systems which rely on perfection in order to achieve strength necessarily fail on scaling to engineering dimensions.

I agree with you. Systems that rely on perfection in order to achieve strength necessarily fail on scaling to engineering dimensions. This is because, in the real world, there is no such thing as perfection. There will always be some degree of variation, whether it is due to manufacturing defects, environmental factors, or simply the fact that we are dealing with complex systems with many interacting parts.

When a system relies on perfection in order to function, even a small deviation from the ideal can cause the system to fail. This is because the system is not designed to handle errors or variations. In contrast, systems that are designed to be robust can withstand a certain amount of variation without failing.

Robust systems are often more complex than systems that rely on perfection. This is because they need to be able to handle a variety of different situations. However, the extra complexity is often worth it, because it makes the system more reliable and less likely to fail.

In conclusion, systems that rely on perfection in order to achieve strength necessarily fail on scaling to engineering dimensions. This is because the real world is not perfect, and systems that are not designed to handle variation will eventually fail.


At least three allotropes of iron occur naturally in bulk form.

that is correct. The three allotropes of iron that occur naturally in bulk form are alpha iron, gamma iron, and delta iron.

Alpha iron is the most stable form of iron at room temperature and atmospheric pressure. It has a body-centered cubic crystal structure and is relatively soft and ductile.

Gamma iron is stable at temperatures above 912°C and has a face-centered cubic crystal structure. It is harder and stronger than alpha iron, but it is also more brittle.

Delta iron is stable at temperatures above 1401°C and has a body-centered cubic crystal structure. It is the hardest and strongest form of iron, but it is also the most brittle.

In addition to these three allotropes, there are a number of other allotropes of iron that can be produced under different conditions. For example, epsilon iron is a metastable allotrope that can be produced at high pressures and low temperatures.


There is no detectable interpretation of the information and misinformation permeating the web.

However, the outcome is expressed coherently.

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