Study showed recently that Google search suggestions may be misleading. The study took the word “nanotechnology” for example and showed that Google frequently directs searcher of this word to topic of health impact of nanotechnology. News reporters said this means that Google may scramble our perception of science reality.

Although I don’t buy the logic that not knowing any topic about the health impact of nanotechnology at all is helpful for a positive public image of nanotechnology, I am still interested what Google suggests for “rheology”. There is a relatively new tool in Google search — the wonder wheel. When searching for “rheology”, you can start a wonder wheel of it and explore the second-order wheel of each suggestion to “rheology”.

To my surprise, “thixotropic” seems much more suggestible than “viscoelastic”. Does this mean people want to know about the former more frequently than the latter? Also more suggestible than “viscoelastic” is the simpler concept “viscosity”. “Viscoelastic” is even not in the suggestion list.

“Viscoelastic” does appears in wider list of suggestion, though.

Viscoelasticity is a fundamental concept in rheology. The study of this property started from the very beginning of the history of rheology until today. However, many that are new to rheology find it much harder to accept than the concept of viscosity or even thixotropy.

The concept of viscosity is simple. The famous Newtonian definition appears exclusively in every textbooks. And starting from this, it is quite easy to understand what is non-Newtonian. Indeed, the Newtoinan/non-Newtonian type of classification is very convenient for fluids — things that can flow, but most rheological problems is concerned by things with fluidity that depends. The abyss most students of rheology really struggling against is things that cannot be properly characterized by only viscosity but need to intorduce the measures of G‘ and G”. I have been asked too many times about the “real, real meaning” of these moduli. Even experienced materials science researchers may not understand why bother uses this complicated framework of measure to characterize a piece material.

No bother indeed, in the practical context. There are two rheometers in my research group. Colleagues from other collages or institutes often find me for rheometry. 90% of the cases are requests for simple viscosity vs shear rate curves. Only when a requester wants to “add more plots and depth” to his/her paper would he/she asked for dynamic, that is, G‘/_G_” tests. In industry, a viscosity curve gives enough information for production in most cases.

The also popular “thixotropy” should thank the industry, too. Thixotropy is hard to characterize in a scientific way (ready for structural modeling) till even today, but materials of this property are essential for the existence of the paint industry, where an ad hoc thixotropic loop test is enough in most cases. More interestingly, while the concept of viscosity cannot meet the cases where the fluidity of materials is dependent, the concept of thixotropy is just about the duality of “flow/don’t flow”, somewhat complementing the former. In the practical sense, it seems that simple extreme concept like flow and not-flow (i.e. Newtonian vs Hookian) is enough in dealing rheological problems. That’s why Google does not suggest “viscoelastic” when searched for “rheology”. This may be misleading, however, when the user wants to know about rheology academically.