I spent several days last week reading drafts of PhD theses from two of my students. I have three PhD students who are scheduled to finish their studies before Easter when they plan to start jobs that they have already been offered. So, there is some urgency to their writing besides the usual desire to finish after three years or more of work on the same topic and the end of their funding. Their relatively undiluted study of their topic can make it difficult for PhD students to see the big picture and write accessible descriptions of their research. I have also encountered this challenge in describing our recent work on integrating digital twins to form an engineering metaverse. There are dozens of published definitions of digital twins whereas the reverse holds for metaverses – no one really knows what they are. Mary Midgley wrote, in her book ‘Beast and Man’, that descriptions should not be an account of everything about an entity or event but just enough to bring to our minds the appropriate conceptual scheme or construct that will tell us everything we need to know. Our challenge as communicators is identifying the conceptual scheme that is needed, in other words selecting what matters and nothing else. I like her example of an inappropriate description: “a section of protoplasm, measuring 1.76 meters vertically, emerged at 2:06 P.M. from hole in building at point x on plan and moved northward, its extremities landing alternately on concrete substratum, finally entering hole in further building, at point y on plan, at 2:09 P.M.” If you need a conceptual scheme to understand this sentence, then try ‘a person walked across the road’.
The concept of digital twins is gaining acceptance and our ability to generate them is advancing [see ‘Digital twins that thrive in the real-world’ on June 9th, 2021]. It is conceivable that we will be able to simulate many real-world systems in the not-too-distant future. Perhaps not in my life-time but possibly in this century we will be able to connect these simulations together to create a computer-generated world. This raises the possibility that other forms of life might have already reached this stage of technology development and that we are living in one of their simulations. We cannot know for certain that we are not in a simulation but equally we cannot know for certain that we are in a simulation. If some other life form had reached the stage of being able to simulate the universe then there is a possibility that they would do it for entertainment, so we might exist inside the equivalent of a teenager’s smart phone, or for scientific exploration in which case we might be inside one of thousands of simulations being performed simultaneously in a lab computer to gather statistical evidence on the development of universes. It seems probable that there would be many more simulations performed for scientific research than for entertainment, so if we are in a simulation then it is more likely that the creator of the simulation is a scientist who is uninterested in this particular one in which we exist. Of course, an alternative scenario is that humans become extinct before reaching the stage of being able to simulate the world or the universe. If extinction occurs as a result of our inability to manage the technological advances, which would allow us to simulate the world, then it seems less likely that other life forms would have avoided this fate and so the probability that we are in a simulation should be reduced. You could also question whether other life forms would have the same motivations or desires to create computer simulations of evolutionary history. There are lots of reasons for doubting that we are in a computer simulation but it does not seem possible to be certain about it.
My research includes work on developing digital twins [see ‘Digital twins that thrive in the real world‘ on June 9th, 2021] of aircraft, power stations and other engineering systems. And I am aware of similar work in other disciplines [see ‘Digital twins could put at risk what it means to be human‘ on November 18th, 2020]; but I was surprised to learn about the demand for digital clothing. Three-dimensional virtual spaces or metaverses exist in computer games, chat rooms and more recently virtual spaces designed for socialising and shopping that are populated by avatars that need to wear something. So, some fashion brands are producing digital clothing and charging you for the privilege of attiring your avatar with their logo. In other words, you can buy clothes that don’t exist for people who are not real. However, DressX has gone a step further producing a ‘digital-only collection’ of clothing for your digital twin or, at the moment, two-dimensional images of real people. So, now you can buy clothes that don’t exist, superimpose them on pictures of real people, and upload the results to social media. Perhaps it’s not as crazy as it seems at first because it might alleviate the need for fast fashion to produce single-use real clothes at enormous cost to the environment. However, dressing up your digital twin does not seem to offer the same level of anticipation and excitement as getting dressed up yourself. (Except in a lockdown? Ed)
Digital twins are becoming ubiquitous in many areas of engineering [see ‘Can you trust your digital twin?‘ on November 23rd, 2016]. Although at the same time, the terminology is becoming blurred as digital shadows and digital models are treated as if they are synonymous with digital twins. A digital model is a digitised replica of physical entity which lacks any automatic data exchange between the entity and its replica. A digital shadow is the digital representation of a physical object with a one-way flow of information from the object to its representation. But a digital twin is a functional representation with a live feedback loop to its counterpart in the real-world. The feedback loop is based on a continuous update to the digital twin about the condition and performance of the physical entity based on data from sensors and on analysis from the digital twin about the performance of the physical entity. This enables a digital twin to provide a service to many stakeholders. For example, the users of a digital twin of an aircraft engine could include the manufacturer, the operator, the maintenance providers and the insurers. These capabilities imply digital twins are themselves becoming products which exist in a digital context that might connect many digital products thus forming an integrated digital environment. I wrote about integrated digital environments when they were a concept and the primary challenges were technical in nature [see ‘Enabling or disruptive technology for nuclear engineering?‘ on January 28th, 2015]. Many of these technical challenges have been resolved and the next set of challenges are economic and commercial ones associated with launching digital twins into global markets that lack adequate understanding, legislation, security, regulation or governance for digital products. In collaboration with my colleagues at the Virtual Engineering Centre, we have recently published a white paper, entitled ‘Transforming digital twins into digital products that thrive in the real world‘ that reviews these issues and identifies the need to establish digital contexts that embrace the social, economic and technical requirements for the appropriate use of digital twins [see ‘Digital twins could put at risk what it means to be human‘ on November 18th, 2020].