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The scientific process is conducted through investigative activities ranging from simple investigations of the surrounding nature to more complicated investigations to predict natural phenomena and solve various problems. Science learning should be carried out with a scientific approach that emphasizes scientific processes in which interactions with technology, the environment, and other sciences fields could not be avoided. Science learning through a STEM (Science, Technology, Engineering, and Mathematics) education approach is among approaches that are world-widely suggested, including in Indonesia, as can be seen in the national curriculum focal points. Unfortunately, as far as our knowledge is concerned, there is no such guide for teachers in implementing STEM education, including suggestions on the real issues and topics of STEM projects related to those issues. In this paper, based on a study of the content of the physics curriculum at the high school level, we propose real problems related to physics contents and possible STEM project topics derived from these fundamental problems. We emphasize topics that are technologically simple and easy to implement nationally, including in remote areas, but pedagogically contain rich aspects of learning.

This preliminary research aims to design instructional material for high school students. The research method used in this development is ADDIE (Analysis, Design, Development, Implementation, and Evaluation). The developed Instructional Material refers to the NGSS (Next Generation Science Standards)’s first dimension. Our design and development stage includes five parts, namely designing and building the equipment, applying the equipment to measure some physical quantities, data analysis, the effectiveness of teaching and learning, and developing lesson plan for teaching and learning. The result of the development is a comprehensive Simple Solar Energy STEM project lesson plan. This project could discuss various integrated topics, processes, or phenomena such as fusion process in a star, greenhouse effects, electromagnetic waves, alternative energy, thermal physics, and lenses which can be depicted in a concept map. The core competencies, time allocation, assessment, and concept map are incorporated into the lesson plan as part of the instructional material. The designed STEM heater project has discrepancies of 16% and 6.8% compared to advanced tools. These discrepancies are tolerable for educational purposes. The STEM Project is also applicable in every school as it is simple and the material is easy to find.

A modification of the Randall-Sundrum metric model in the form of conformally flat metric was proposed some years ago. The proposed model shows better localization properties than the original Randall-Sundrum model. However, this new model still does not meet the expectation that all fundamental fields can be localized for one type of warp factor, e.g. for a decreasing warp factor. In this research we propose to add a factor f(r) in the extra coordinate part of the above modified Randall-Sundrum metric and derive conditions for localization for scalar and vector fields. r is the extra coordinate. We then look for some functions f(r) that fulfill the localization conditions for both scalar and vector fields. Examples of the function f(r) under investigation are e Ar, e −Ar−Br 2 , e −A/r , Ar, Ar + Br 2, and sinh(Ar). We found the expected function, that is e Ar , which might be used as a further discussion in fields localization.

The braneworld model provides a solution to the hierarchy problem in cosmology. Based on its thickness, braneworld models are classified into a thin brane model (RandallSundrum (RS) and the RS-like models) and a thick brane model. The thin brane model has a problem according to the zero-width brane and some fields localization. Meanwhile, thick brane is quite good in explaining fields localization and there is no problem related to brane thickness. In this article, we re-examine the thick brane in a modified gravity, that is f(R,T) gravity. The equation of motion for the y-dependence scalar field and the f(R,T) field equation for a conformally flat brane and Robertson-Walker brane are derived. We also investigate the localization of scalar field on the f(R,T) thick brane, for a specific f(R,T) form. As the results, the formulation of Robertson-Walker thick brane is obtained. It can be reduced and has similarities to the previous f(R,T) brane consideration. It has a possibility to trap the field ϕ(y) in a thick brane with specific conditions of brane’s scale factor. It was shown that the expanding or contracting universe affects the localization conditions of the scalar fields.

One contribution of Einstein’s equation is the existence of gravitational waves. The weak gravitational waves are solutions of the linearized Einstein’s equation around a Minkowski spacetime. By using a certain coordinate freedom, waves propagate at the speed of light and propagating plane waves in z-direction gives two polarization states. The geodesic equation gives an oscillating proper distance of two rest particles when gravitational wave passes, while for proper time, no time dilatation meaning each particle has the same proper time. The fluctuation effect of gravitational waves causes ripples in spacetime making each particle feels a tidal acceleration.

We study the localization properties of spinor field coupled to scalar field through Yukawa coupling in a Modified Randall-Sundrum (MRS) model. We derive general localization conditions and solve the solution of the field equation corresponding to the extra coordinate and match the solution to the localization conditions. We obtain that the spinor and scalar fields are localizable on the MRS brane for specific conditions with a decreasing warp factor.

Using Hamilton-Jacobi method, we study the Dirac particles emission from Reissner-Nordstrom-Vaidya (RNV) black hole. The Dirac particles are described by Dirac equation in curved spacetime and emission process is defined as tunneling effect. The probability of Dirac particles emission is related to the Hawking temperature and we obtain that this temperature is equal to temperature that derived through spinless particles emission. Furthermore, we also show that the mass of Dirac particles does not affect to the Hawking temperature.